diff --git a/reactos/boot/freeldr/freeldr/arch/i386/archmach.c b/reactos/boot/freeldr/freeldr/arch/i386/archmach.c
index c8171b0208c..d09f1dde2bb 100644
--- a/reactos/boot/freeldr/freeldr/arch/i386/archmach.c
+++ b/reactos/boot/freeldr/freeldr/arch/i386/archmach.c
@@ -27,7 +27,7 @@
 #include "rtl.h"
 
 VOID
-MachInit(char *CmdLine)
+MachInit(const char *CmdLine)
 {
   ULONG PciId;
 
diff --git a/reactos/boot/freeldr/freeldr/arch/i386/machpc.c b/reactos/boot/freeldr/freeldr/arch/i386/machpc.c
index eae1bb06995..dce27b27f83 100644
--- a/reactos/boot/freeldr/freeldr/arch/i386/machpc.c
+++ b/reactos/boot/freeldr/freeldr/arch/i386/machpc.c
@@ -26,7 +26,7 @@
 #include "i386.h"
 
 VOID
-PcMachInit(char *CmdLine)
+PcMachInit(const char *CmdLine)
 {
   EnableA20();
 
diff --git a/reactos/boot/freeldr/freeldr/arch/i386/machpc.h b/reactos/boot/freeldr/freeldr/arch/i386/machpc.h
index 7a2a6eb58b8..85c9ca850d1 100644
--- a/reactos/boot/freeldr/freeldr/arch/i386/machpc.h
+++ b/reactos/boot/freeldr/freeldr/arch/i386/machpc.h
@@ -26,7 +26,7 @@
 #include "mm.h"
 #endif
 
-VOID PcMachInit(char *CmdLine);
+VOID PcMachInit(const char *CmdLine);
 
 VOID PcConsPutChar(int Ch);
 BOOL PcConsKbHit();
diff --git a/reactos/boot/freeldr/freeldr/arch/i386/machxbox.c b/reactos/boot/freeldr/freeldr/arch/i386/machxbox.c
index fe3c6dbccd7..bf4df218a75 100644
--- a/reactos/boot/freeldr/freeldr/arch/i386/machxbox.c
+++ b/reactos/boot/freeldr/freeldr/arch/i386/machxbox.c
@@ -24,7 +24,7 @@
 #include "i386.h"
 
 VOID
-XboxMachInit(char *CmdLine)
+XboxMachInit(const char *CmdLine)
 {
   /* Initialize our stuff */
   XboxMemInit();
diff --git a/reactos/boot/freeldr/freeldr/arch/i386/machxbox.h b/reactos/boot/freeldr/freeldr/arch/i386/machxbox.h
index d82cdc8f246..641852e02a4 100644
--- a/reactos/boot/freeldr/freeldr/arch/i386/machxbox.h
+++ b/reactos/boot/freeldr/freeldr/arch/i386/machxbox.h
@@ -26,7 +26,7 @@
 
 UCHAR XboxFont8x16[256 * 16];
 
-VOID XboxMachInit(char *CmdLine);
+VOID XboxMachInit(const char *CmdLine);
 
 VOID XboxConsPutChar(int Ch);
 BOOL XboxConsKbHit();
diff --git a/reactos/boot/freeldr/freeldr/arch/powerpc/mach.c b/reactos/boot/freeldr/freeldr/arch/powerpc/mach.c
index fcdd6fa2728..efd6addc775 100644
--- a/reactos/boot/freeldr/freeldr/arch/powerpc/mach.c
+++ b/reactos/boot/freeldr/freeldr/arch/powerpc/mach.c
@@ -279,7 +279,7 @@ void PpcInit( of_proxy the_ofproxy ) {
     BootMain("freeldr-ppc");
 }
 
-void MachInit(char *CmdLine) {
+void MachInit(const char *CmdLine) {
     int len;
     printf( "Determining boot device:\n" );
     len = ofw_getprop(chosen_package, "bootpath",
diff --git a/reactos/boot/freeldr/freeldr/bootmgr.c b/reactos/boot/freeldr/freeldr/bootmgr.c
index fad99cc42af..896f7a6fe13 100644
--- a/reactos/boot/freeldr/freeldr/bootmgr.c
+++ b/reactos/boot/freeldr/freeldr/bootmgr.c
@@ -43,8 +43,8 @@ VOID RunLoader(VOID)
 	CHAR	SettingValue[80];
 	ULONG		SectionId;
 	ULONG		OperatingSystemCount;
-	PCHAR	*OperatingSystemSectionNames;
-	PCHAR	*OperatingSystemDisplayNames;
+	PCSTR	*OperatingSystemSectionNames;
+	PCSTR	*OperatingSystemDisplayNames;
 	ULONG		DefaultOperatingSystem;
 	LONG		TimeOut;
 	ULONG		SelectedOperatingSystem;
@@ -166,10 +166,10 @@ reboot:
 	return;
 }
 
-ULONG	 GetDefaultOperatingSystem(PCHAR OperatingSystemList[], ULONG	 OperatingSystemCount)
+ULONG	 GetDefaultOperatingSystem(PCSTR OperatingSystemList[], ULONG	 OperatingSystemCount)
 {
 	CHAR	DefaultOSText[80];
-	PCHAR	DefaultOSName;
+	PCSTR	DefaultOSName;
 	ULONG	SectionId;
 	ULONG	DefaultOS = 0;
 	ULONG	Idx;
diff --git a/reactos/boot/freeldr/freeldr/cmdline.c b/reactos/boot/freeldr/freeldr/cmdline.c
index 66a28b6caf2..b6f42937936 100644
--- a/reactos/boot/freeldr/freeldr/cmdline.c
+++ b/reactos/boot/freeldr/freeldr/cmdline.c
@@ -106,7 +106,7 @@ CmdLineParse(char *CmdLine)
     }
 }
 
-char *
+const char *
 CmdLineGetDefaultOS(void)
 {
   return CmdLineInfo.DefaultOperatingSystem;
diff --git a/reactos/boot/freeldr/freeldr/custom.c b/reactos/boot/freeldr/freeldr/custom.c
index 09938baeecb..190d2c82ed7 100644
--- a/reactos/boot/freeldr/freeldr/custom.c
+++ b/reactos/boot/freeldr/freeldr/custom.c
@@ -32,20 +32,20 @@
 #include <machine.h>
 
 
-CHAR	BootDrivePrompt[] = "Enter the boot drive.\n\nExamples:\nfd0 - first floppy drive\nhd0 - first hard drive\nhd1 - second hard drive\ncd0 - first CD-ROM drive.\n\nBIOS drive numbers may also be used:\n0 - first floppy drive\n0x80 - first hard drive\n0x81 - second hard drive";
-CHAR	BootPartitionPrompt[] = "Enter the boot partition.\n\nEnter 0 for the active (bootable) partition.";
-CHAR	BootSectorFilePrompt[] = "Enter the boot sector file path.\n\nExamples:\n\\BOOTSECT.DOS\n/boot/bootsect.dos";
-CHAR	LinuxKernelPrompt[] = "Enter the Linux kernel image path.\n\nExamples:\n/vmlinuz\n/boot/vmlinuz-2.4.18";
-CHAR	LinuxInitrdPrompt[] = "Enter the initrd image path.\n\nExamples:\n/initrd.gz\n/boot/root.img.gz\n\nLeave blank for no initial ram disk.";
-CHAR	LinuxCommandLinePrompt[] = "Enter the Linux kernel command line.\n\nExamples:\nroot=/dev/hda1\nroot=/dev/fd0 read-only\nroot=/dev/sdb1 init=/sbin/init";
-CHAR	ReactOSSystemPathPrompt[] = "Enter the path to your ReactOS system directory.\n\nExamples:\n\\REACTOS\n\\ROS";
-CHAR	ReactOSOptionsPrompt[] = "Enter the options you want passed to the kernel.\n\nExamples:\n/DEBUG /DEBUGPORT=COM1 /BAUDRATE=115200\n/FASTDETECT /SOS /NOGUIBOOT\n/BASEVIDEO /MAXMEM=64\n/KERNEL=NTKRNLMP.EXE /HAL=HALMPS.DLL";
+const CHAR	BootDrivePrompt[] = "Enter the boot drive.\n\nExamples:\nfd0 - first floppy drive\nhd0 - first hard drive\nhd1 - second hard drive\ncd0 - first CD-ROM drive.\n\nBIOS drive numbers may also be used:\n0 - first floppy drive\n0x80 - first hard drive\n0x81 - second hard drive";
+const CHAR	BootPartitionPrompt[] = "Enter the boot partition.\n\nEnter 0 for the active (bootable) partition.";
+const CHAR	BootSectorFilePrompt[] = "Enter the boot sector file path.\n\nExamples:\n\\BOOTSECT.DOS\n/boot/bootsect.dos";
+const CHAR	LinuxKernelPrompt[] = "Enter the Linux kernel image path.\n\nExamples:\n/vmlinuz\n/boot/vmlinuz-2.4.18";
+const CHAR 	LinuxInitrdPrompt[] = "Enter the initrd image path.\n\nExamples:\n/initrd.gz\n/boot/root.img.gz\n\nLeave blank for no initial ram disk.";
+const CHAR	LinuxCommandLinePrompt[] = "Enter the Linux kernel command line.\n\nExamples:\nroot=/dev/hda1\nroot=/dev/fd0 read-only\nroot=/dev/sdb1 init=/sbin/init";
+const CHAR	ReactOSSystemPathPrompt[] = "Enter the path to your ReactOS system directory.\n\nExamples:\n\\REACTOS\n\\ROS";
+const CHAR	ReactOSOptionsPrompt[] = "Enter the options you want passed to the kernel.\n\nExamples:\n/DEBUG /DEBUGPORT=COM1 /BAUDRATE=115200\n/FASTDETECT /SOS /NOGUIBOOT\n/BASEVIDEO /MAXMEM=64\n/KERNEL=NTKRNLMP.EXE /HAL=HALMPS.DLL";
 
-CHAR	CustomBootPrompt[] = "Press ENTER to boot your custom boot setup.";
+const CHAR	CustomBootPrompt[] = "Press ENTER to boot your custom boot setup.";
 
 VOID OptionMenuCustomBoot(VOID)
 {
-	PCHAR	CustomBootMenuList[] = { "Disk", "Partition", "Boot Sector File", "ReactOS", "Linux" };
+	PCSTR	CustomBootMenuList[] = { "Disk", "Partition", "Boot Sector File", "ReactOS", "Linux" };
 	ULONG		CustomBootMenuCount = sizeof(CustomBootMenuList) / sizeof(CustomBootMenuList[0]);
 	ULONG		SelectedMenuItem;
 
diff --git a/reactos/boot/freeldr/freeldr/disk/disk.c b/reactos/boot/freeldr/freeldr/disk/disk.c
index 600cff3e73c..d3e79c38118 100644
--- a/reactos/boot/freeldr/freeldr/disk/disk.c
+++ b/reactos/boot/freeldr/freeldr/disk/disk.c
@@ -39,7 +39,7 @@ VOID DiskReportError (BOOL bError)
 	bReportError = bError;
 }
 
-VOID DiskError(PCHAR ErrorString, ULONG ErrorCode)
+VOID DiskError(PCSTR ErrorString, ULONG ErrorCode)
 {
 	CHAR	ErrorCodeString[200];
 
@@ -53,7 +53,7 @@ VOID DiskError(PCHAR ErrorString, ULONG ErrorCode)
 	UiMessageBox(ErrorCodeString);
 }
 
-PCHAR DiskGetErrorCodeString(ULONG ErrorCode)
+PCSTR DiskGetErrorCodeString(ULONG ErrorCode)
 {
 	switch (ErrorCode)
 	{
diff --git a/reactos/boot/freeldr/freeldr/drivemap.c b/reactos/boot/freeldr/freeldr/drivemap.c
index 0486ca3e16a..e889024ce03 100644
--- a/reactos/boot/freeldr/freeldr/drivemap.c
+++ b/reactos/boot/freeldr/freeldr/drivemap.c
@@ -30,7 +30,7 @@ ULONG		OldInt13HandlerAddress = 0;	// Address of BIOS int 13h handler
 ULONG		DriveMapHandlerAddress = 0;	// Linear address of our drive map handler
 ULONG		DriveMapHandlerSegOff = 0;	// Segment:offset style address of our drive map handler
 
-VOID DriveMapMapDrivesInSection(PCHAR SectionName)
+VOID DriveMapMapDrivesInSection(PCSTR SectionName)
 {
 	CHAR			SettingName[80];
 	CHAR			SettingValue[80];
@@ -117,7 +117,7 @@ VOID DriveMapMapDrivesInSection(PCHAR SectionName)
 	}
 }
 
-BOOL DriveMapIsValidDriveString(PCHAR DriveString)
+BOOL DriveMapIsValidDriveString(PCSTR DriveString)
 {
 	ULONG		Index;
 
@@ -147,7 +147,7 @@ BOOL DriveMapIsValidDriveString(PCHAR DriveString)
 	return TRUE;
 }
 
-ULONG DriveMapGetBiosDriveNumber(PCHAR DeviceName)
+ULONG DriveMapGetBiosDriveNumber(PCSTR DeviceName)
 {
 	ULONG		BiosDriveNumber = 0;
 
diff --git a/reactos/boot/freeldr/freeldr/freeldr.c b/reactos/boot/freeldr/freeldr/freeldr.c
index 54e8638bbef..407b709c0f8 100644
--- a/reactos/boot/freeldr/freeldr/freeldr.c
+++ b/reactos/boot/freeldr/freeldr/freeldr.c
@@ -27,7 +27,7 @@
 #include <fs.h>
 #include <cmdline.h>
 
-VOID BootMain(char *CmdLine)
+VOID BootMain(LPSTR CmdLine)
 {
 	CmdLineParse(CmdLine);
 
diff --git a/reactos/boot/freeldr/freeldr/fs/ext2.c b/reactos/boot/freeldr/freeldr/fs/ext2.c
index b8ff14f935c..5473c54ff3a 100644
--- a/reactos/boot/freeldr/freeldr/fs/ext2.c
+++ b/reactos/boot/freeldr/freeldr/fs/ext2.c
@@ -87,7 +87,7 @@ BOOL Ext2OpenVolume(UCHAR DriveNumber, ULONGLONG VolumeStartSector)
  * Tries to open the file 'name' and returns true or false
  * for success and failure respectively
  */
-FILE* Ext2OpenFile(PCHAR FileName)
+FILE* Ext2OpenFile(PCSTR FileName)
 {
 	EXT2_FILE_INFO		TempExt2FileInfo;
 	PEXT2_FILE_INFO		FileHandle;
@@ -190,7 +190,7 @@ FILE* Ext2OpenFile(PCHAR FileName)
  * with info describing the file, etc. returns true
  * if the file exists or false otherwise
  */
-BOOL Ext2LookupFile(PCHAR FileName, PEXT2_FILE_INFO Ext2FileInfoPointer)
+BOOL Ext2LookupFile(PCSTR FileName, PEXT2_FILE_INFO Ext2FileInfoPointer)
 {
 	UINT				i;
 	ULONG				NumberOfPathParts;
diff --git a/reactos/boot/freeldr/freeldr/fs/ext2.h b/reactos/boot/freeldr/freeldr/fs/ext2.h
index 84d1a21818a..5d033b7280a 100644
--- a/reactos/boot/freeldr/freeldr/fs/ext2.h
+++ b/reactos/boot/freeldr/freeldr/fs/ext2.h
@@ -667,8 +667,8 @@ typedef struct
 
 
 BOOL	Ext2OpenVolume(UCHAR DriveNumber, ULONGLONG VolumeStartSector);
-FILE*	Ext2OpenFile(PCHAR FileName);
-BOOL	Ext2LookupFile(PCHAR FileName, PEXT2_FILE_INFO Ext2FileInfoPointer);
+FILE*	Ext2OpenFile(PCSTR FileName);
+BOOL	Ext2LookupFile(PCSTR FileName, PEXT2_FILE_INFO Ext2FileInfoPointer);
 BOOL	Ext2SearchDirectoryBufferForFile(PVOID DirectoryBuffer, ULONG DirectorySize, PCHAR FileName, PEXT2_DIR_ENTRY DirectoryEntry);
 BOOL	Ext2ReadFile(FILE *FileHandle, ULONGLONG BytesToRead, ULONGLONG* BytesRead, PVOID Buffer);
 ULONGLONG		Ext2GetFileSize(FILE *FileHandle);
diff --git a/reactos/boot/freeldr/freeldr/fs/fat.c b/reactos/boot/freeldr/freeldr/fs/fat.c
index 278f664716b..714fa8668ef 100644
--- a/reactos/boot/freeldr/freeldr/fs/fat.c
+++ b/reactos/boot/freeldr/freeldr/fs/fat.c
@@ -687,7 +687,7 @@ static BOOL FatXSearchDirectoryBufferForFile(PVOID DirectoryBuffer, ULONG Direct
  * with info describing the file, etc. returns true
  * if the file exists or false otherwise
  */
-BOOL FatLookupFile(PCHAR FileName, PFAT_FILE_INFO FatFileInfoPointer)
+BOOL FatLookupFile(PCSTR FileName, PFAT_FILE_INFO FatFileInfoPointer)
 {
 	UINT		i;
 	ULONG		NumberOfPathParts;
@@ -915,7 +915,7 @@ BOOL FatGetFatEntry(ULONG Cluster, ULONG* ClusterPointer)
  * Tries to open the file 'name' and returns true or false
  * for success and failure respectively
  */
-FILE* FatOpenFile(PCHAR FileName)
+FILE* FatOpenFile(PCSTR FileName)
 {
 	FAT_FILE_INFO		TempFatFileInfo;
 	PFAT_FILE_INFO		FileHandle;
diff --git a/reactos/boot/freeldr/freeldr/fs/fat.h b/reactos/boot/freeldr/freeldr/fs/fat.h
index 6a24bbfdbc4..a57ed0b4158 100644
--- a/reactos/boot/freeldr/freeldr/fs/fat.h
+++ b/reactos/boot/freeldr/freeldr/fs/fat.h
@@ -156,10 +156,10 @@ BOOL	FatOpenVolume(ULONG DriveNumber, ULONG VolumeStartSector, ULONG PartitionSe
 ULONG	FatDetermineFatType(PFAT_BOOTSECTOR FatBootSector, ULONG PartitionSectorCount);
 PVOID	FatBufferDirectory(ULONG DirectoryStartCluster, ULONG* EntryCountPointer, BOOL RootDirectory);
 BOOL	FatSearchDirectoryBufferForFile(PVOID DirectoryBuffer, ULONG EntryCount, PCHAR FileName, PFAT_FILE_INFO FatFileInfoPointer);
-BOOL	FatLookupFile(PCHAR FileName, PFAT_FILE_INFO FatFileInfoPointer);
+BOOL	FatLookupFile(PCSTR FileName, PFAT_FILE_INFO FatFileInfoPointer);
 void	FatParseShortFileName(PCHAR Buffer, PDIRENTRY DirEntry);
 BOOL	FatGetFatEntry(ULONG Cluster, ULONG* ClusterPointer);
-FILE*	FatOpenFile(PCHAR FileName);
+FILE*	FatOpenFile(PCSTR FileName);
 ULONG	FatCountClustersInChain(ULONG StartCluster);
 ULONG*	FatGetClusterChainArray(ULONG StartCluster);
 BOOL	FatReadCluster(ULONG ClusterNumber, PVOID Buffer);
diff --git a/reactos/boot/freeldr/freeldr/fs/fs.c b/reactos/boot/freeldr/freeldr/fs/fs.c
index b197d840a7d..f2aabe257cd 100644
--- a/reactos/boot/freeldr/freeldr/fs/fs.c
+++ b/reactos/boot/freeldr/freeldr/fs/fs.c
@@ -42,7 +42,7 @@ ULONG			FsType = 0;	// Type of filesystem on boot device, set by FsOpenVolume()
 // FUNCTIONS
 /////////////////////////////////////////////////////////////////////////////////////////////
 
-VOID FileSystemError(PCHAR ErrorString)
+VOID FileSystemError(PCSTR ErrorString)
 {
 	DbgPrint((DPRINT_FILESYSTEM, "%s\n", ErrorString));
 
@@ -123,7 +123,7 @@ BOOL FsOpenSystemVolume(char *SystemPath, char *RemainingPath, PULONG Device)
 }
 
 
-PFILE FsOpenFile(PCHAR FileName)
+PFILE FsOpenFile(PCSTR FileName)
 {
 	PFILE	FileHandle = NULL;
 
@@ -337,7 +337,7 @@ BOOL FsIsEndOfFile(PFILE FileHandle)
  * This function parses a path in the form of dir1\dir2\file1.ext
  * and returns the number of parts it has (i.e. 3 - dir1,dir2,file1.ext)
  */
-ULONG FsGetNumPathParts(PCHAR Path)
+ULONG FsGetNumPathParts(PCSTR Path)
 {
 	size_t		i;
 	ULONG		num;
@@ -362,7 +362,7 @@ ULONG FsGetNumPathParts(PCHAR Path)
  * and puts the first name of the path (e.g. "dir1") in buffer
  * compatible with the MSDOS directory structure
  */
-VOID FsGetFirstNameFromPath(PCHAR Buffer, PCHAR Path)
+VOID FsGetFirstNameFromPath(PCHAR Buffer, PCSTR Path)
 {
 	size_t		i;
 
diff --git a/reactos/boot/freeldr/freeldr/fs/iso.c b/reactos/boot/freeldr/freeldr/fs/iso.c
index 81ddecfa7ac..157e81f41d5 100644
--- a/reactos/boot/freeldr/freeldr/fs/iso.c
+++ b/reactos/boot/freeldr/freeldr/fs/iso.c
@@ -180,7 +180,7 @@ static PVOID IsoBufferDirectory(ULONG DirectoryStartSector, ULONG DirectoryLengt
  * with info describing the file, etc. returns true
  * if the file exists or false otherwise
  */
-static BOOL IsoLookupFile(PCHAR FileName, PISO_FILE_INFO IsoFileInfoPointer)
+static BOOL IsoLookupFile(PCSTR FileName, PISO_FILE_INFO IsoFileInfoPointer)
 {
 	UINT		i;
 	ULONG			NumberOfPathParts;
@@ -263,7 +263,7 @@ static BOOL IsoLookupFile(PCHAR FileName, PISO_FILE_INFO IsoFileInfoPointer)
  * Tries to open the file 'name' and returns true or false
  * for success and failure respectively
  */
-FILE* IsoOpenFile(PCHAR FileName)
+FILE* IsoOpenFile(PCSTR FileName)
 {
 	ISO_FILE_INFO		TempFileInfo;
 	PISO_FILE_INFO		FileHandle;
diff --git a/reactos/boot/freeldr/freeldr/fs/iso.h b/reactos/boot/freeldr/freeldr/fs/iso.h
index e0be69bcaad..9cde9a8c9d5 100644
--- a/reactos/boot/freeldr/freeldr/fs/iso.h
+++ b/reactos/boot/freeldr/freeldr/fs/iso.h
@@ -106,7 +106,7 @@ typedef struct
 
 
 BOOL	IsoOpenVolume(ULONG DriveNumber);
-FILE*	IsoOpenFile(PCHAR FileName);
+FILE*	IsoOpenFile(PCSTR FileName);
 BOOL	IsoReadFile(FILE *FileHandle, ULONG BytesToRead, ULONG* BytesRead, PVOID Buffer);
 ULONG		IsoGetFileSize(FILE *FileHandle);
 VOID	IsoSetFilePointer(FILE *FileHandle, ULONG NewFilePointer);
diff --git a/reactos/boot/freeldr/freeldr/fs/ntfs.c b/reactos/boot/freeldr/freeldr/fs/ntfs.c
index 4861d6c86ef..555738ecea2 100644
--- a/reactos/boot/freeldr/freeldr/fs/ntfs.c
+++ b/reactos/boot/freeldr/freeldr/fs/ntfs.c
@@ -87,7 +87,7 @@ static PUCHAR NtfsDecodeRun(PUCHAR DataRun, LONGLONG *DataRunOffset, ULONGLONG *
 }
 
 /* FIXME: Add support for attribute lists! */
-static BOOL NtfsFindAttribute(PNTFS_ATTR_CONTEXT Context, PNTFS_MFT_RECORD MftRecord, ULONG Type, PWCHAR Name)
+static BOOL NtfsFindAttribute(PNTFS_ATTR_CONTEXT Context, PNTFS_MFT_RECORD MftRecord, ULONG Type, const WCHAR *Name)
 {
     PNTFS_ATTR_RECORD AttrRecord;
     PNTFS_ATTR_RECORD AttrRecordEnd;
@@ -563,7 +563,7 @@ static BOOL NtfsFindMftRecord(ULONG MFTIndex, PCHAR FileName, ULONG *OutMFTIndex
     return FALSE;
 }
 
-static BOOL NtfsLookupFile(PCHAR FileName, PNTFS_MFT_RECORD MftRecord, PNTFS_ATTR_CONTEXT DataContext)
+static BOOL NtfsLookupFile(PCSTR FileName, PNTFS_MFT_RECORD MftRecord, PNTFS_ATTR_CONTEXT DataContext)
 {
     ULONG NumberOfPathParts;
     CHAR PathPart[261];
@@ -680,7 +680,7 @@ BOOL NtfsOpenVolume(ULONG DriveNumber, ULONG VolumeStartSector)
     return TRUE;
 }
 
-FILE* NtfsOpenFile(PCHAR FileName)
+FILE* NtfsOpenFile(PCSTR FileName)
 {
     PNTFS_FILE_HANDLE FileHandle;
     PNTFS_MFT_RECORD MftRecord;
diff --git a/reactos/boot/freeldr/freeldr/fs/ntfs.h b/reactos/boot/freeldr/freeldr/fs/ntfs.h
index 870ac857228..fe04ac7ea29 100644
--- a/reactos/boot/freeldr/freeldr/fs/ntfs.h
+++ b/reactos/boot/freeldr/freeldr/fs/ntfs.h
@@ -219,7 +219,7 @@ typedef struct
 } PACKED NTFS_FILE_HANDLE, *PNTFS_FILE_HANDLE;
 
 BOOL	NtfsOpenVolume(ULONG DriveNumber, ULONG VolumeStartSector);
-FILE*	NtfsOpenFile(PCHAR FileName);
+FILE*	NtfsOpenFile(PCSTR FileName);
 BOOL	NtfsReadFile(FILE *FileHandle, ULONG BytesToRead, ULONG* BytesRead, PVOID Buffer);
 ULONG	NtfsGetFileSize(FILE *FileHandle);
 VOID	NtfsSetFilePointer(FILE *FileHandle, ULONG NewFilePointer);
diff --git a/reactos/boot/freeldr/freeldr/include/bootmgr.h b/reactos/boot/freeldr/freeldr/include/bootmgr.h
index 2a3e3e9a7b7..9945c9fdf82 100644
--- a/reactos/boot/freeldr/freeldr/include/bootmgr.h
+++ b/reactos/boot/freeldr/freeldr/include/bootmgr.h
@@ -21,7 +21,7 @@
 #define __BOOTMGR_H
 
 
-ULONG		GetDefaultOperatingSystem(PCHAR OperatingSystemList[], ULONG OperatingSystemCount);
+ULONG		GetDefaultOperatingSystem(PCSTR OperatingSystemList[], ULONG OperatingSystemCount);
 LONG		GetTimeOut(VOID);
 BOOL	MainBootMenuKeyPressFilter(ULONG KeyPress);
 
diff --git a/reactos/boot/freeldr/freeldr/include/cmdline.h b/reactos/boot/freeldr/freeldr/include/cmdline.h
index 5bfc3ff84bf..36849a4a786 100644
--- a/reactos/boot/freeldr/freeldr/include/cmdline.h
+++ b/reactos/boot/freeldr/freeldr/include/cmdline.h
@@ -23,14 +23,14 @@
 
 typedef struct tagCMDLINEINFO
 {
-  char *DefaultOperatingSystem;
+  const char *DefaultOperatingSystem;
   LONG TimeOut;
 } CMDLINEINFO, *PCMDLINEINFO;
 
-extern void CmdLineParse(char *CmdLine);
+void CmdLineParse(char *CmdLine);
 
-extern char *CmdLineGetDefaultOS(void);
-extern LONG CmdLineGetTimeOut(void);
+const char *CmdLineGetDefaultOS(void);
+LONG CmdLineGetTimeOut(void);
 
 #endif /* __CMDLINE_H__ */
 
diff --git a/reactos/boot/freeldr/freeldr/include/disk.h b/reactos/boot/freeldr/freeldr/include/disk.h
index 254d70f2903..a1aee258215 100644
--- a/reactos/boot/freeldr/freeldr/include/disk.h
+++ b/reactos/boot/freeldr/freeldr/include/disk.h
@@ -119,8 +119,8 @@ BOOL	DiskGetExtendedDriveParameters(ULONG DriveNumber, PVOID Buffer, USHORT Buff
 //
 ///////////////////////////////////////////////////////////////////////////////////////
 VOID	DiskReportError (BOOL bError);
-VOID	DiskError(PCHAR ErrorString, ULONG ErrorCode);
-PCHAR	DiskGetErrorCodeString(ULONG ErrorCode);
+VOID	DiskError(PCSTR ErrorString, ULONG ErrorCode);
+PCSTR	DiskGetErrorCodeString(ULONG ErrorCode);
 BOOL	DiskReadLogicalSectors(ULONG DriveNumber, ULONGLONG SectorNumber, ULONG SectorCount, PVOID Buffer); // Implemented in i386disk.c
 BOOL	DiskIsDriveRemovable(ULONG DriveNumber);
 VOID	DiskStopFloppyMotor(VOID);	// Implemented in i386disk.c
diff --git a/reactos/boot/freeldr/freeldr/include/drivemap.h b/reactos/boot/freeldr/freeldr/include/drivemap.h
index e2d19cbad75..11d6a1b03cb 100644
--- a/reactos/boot/freeldr/freeldr/include/drivemap.h
+++ b/reactos/boot/freeldr/freeldr/include/drivemap.h
@@ -29,9 +29,9 @@ typedef struct
 
 } PACKED DRIVE_MAP_LIST, *PDRIVE_MAP_LIST;
 
-VOID	DriveMapMapDrivesInSection(PCHAR SectionName);
-BOOL	DriveMapIsValidDriveString(PCHAR DriveString);			// Checks the drive string ("hd0") for validity
-ULONG		DriveMapGetBiosDriveNumber(PCHAR DeviceName);			// Returns a BIOS drive number for any given device name (e.g. 0x80 for 'hd0')
+VOID	DriveMapMapDrivesInSection(PCSTR SectionName);
+BOOL	DriveMapIsValidDriveString(PCSTR DriveString);			// Checks the drive string ("hd0") for validity
+ULONG		DriveMapGetBiosDriveNumber(PCSTR DeviceName);			// Returns a BIOS drive number for any given device name (e.g. 0x80 for 'hd0')
 VOID	DriveMapInstallInt13Handler(PDRIVE_MAP_LIST DriveMap);	// Installs the int 13h handler for the drive mapper
 VOID	DriveMapRemoveInt13Handler(VOID);						// Removes a previously installed int 13h drive map handler
 
diff --git a/reactos/boot/freeldr/freeldr/include/fs.h b/reactos/boot/freeldr/freeldr/include/fs.h
index 4b2bb6ee37c..4f368f28311 100644
--- a/reactos/boot/freeldr/freeldr/include/fs.h
+++ b/reactos/boot/freeldr/freeldr/include/fs.h
@@ -32,17 +32,17 @@
 #define FILE			VOID
 #define PFILE			FILE *
 
-VOID	FileSystemError(PCHAR ErrorString);
+VOID	FileSystemError(PCSTR ErrorString);
 BOOL	FsOpenBootVolume();
 BOOL	FsOpenSystemVolume(PCHAR SystemPath, PCHAR RemainingPath, PULONG BootDevice);
-PFILE	FsOpenFile(PCHAR FileName);
+PFILE	FsOpenFile(PCSTR FileName);
 VOID	FsCloseFile(PFILE FileHandle);
 BOOL	FsReadFile(PFILE FileHandle, ULONG BytesToRead, ULONG* BytesRead, PVOID Buffer);
 ULONG		FsGetFileSize(PFILE FileHandle);
 VOID	FsSetFilePointer(PFILE FileHandle, ULONG NewFilePointer);
 ULONG		FsGetFilePointer(PFILE FileHandle);
 BOOL	FsIsEndOfFile(PFILE FileHandle);
-ULONG		FsGetNumPathParts(PCHAR Path);
-VOID	FsGetFirstNameFromPath(PCHAR Buffer, PCHAR Path);
+ULONG		FsGetNumPathParts(PCSTR Path);
+VOID	FsGetFirstNameFromPath(PCHAR Buffer, PCSTR Path);
 
 #endif // #defined __FS_H
diff --git a/reactos/boot/freeldr/freeldr/include/inifile.h b/reactos/boot/freeldr/freeldr/include/inifile.h
index 6c03574737b..2fd46235786 100644
--- a/reactos/boot/freeldr/freeldr/include/inifile.h
+++ b/reactos/boot/freeldr/freeldr/include/inifile.h
@@ -22,14 +22,14 @@
 
 BOOL	IniFileInitialize(VOID);
 
-BOOL	IniOpenSection(PCHAR SectionName, ULONG* SectionId);
+BOOL	IniOpenSection(PCSTR SectionName, ULONG* SectionId);
 ULONG		IniGetNumSectionItems(ULONG SectionId);
 ULONG		IniGetSectionSettingNameSize(ULONG SectionId, ULONG SettingIndex);
 ULONG		IniGetSectionSettingValueSize(ULONG SectionId, ULONG SettingIndex);
 BOOL	IniReadSettingByNumber(ULONG SectionId, ULONG SettingNumber, PCHAR SettingName, ULONG NameSize, PCHAR SettingValue, ULONG ValueSize);
-BOOL	IniReadSettingByName(ULONG SectionId, PCHAR SettingName, PCHAR Buffer, ULONG BufferSize);
-BOOL	IniAddSection(PCHAR SectionName, ULONG* SectionId);
-BOOL	IniAddSettingValueToSection(ULONG SectionId, PCHAR SettingName, PCHAR SettingValue);
+BOOL	IniReadSettingByName(ULONG SectionId, PCSTR SettingName, PCHAR Buffer, ULONG BufferSize);
+BOOL	IniAddSection(PCSTR SectionName, ULONG* SectionId);
+BOOL	IniAddSettingValueToSection(ULONG SectionId, PCSTR SettingName, PCSTR SettingValue);
 
 
 #endif // defined __PARSEINI_H
diff --git a/reactos/boot/freeldr/freeldr/include/linux.h b/reactos/boot/freeldr/freeldr/include/linux.h
index 2d12a54e205..c518933bb9b 100644
--- a/reactos/boot/freeldr/freeldr/include/linux.h
+++ b/reactos/boot/freeldr/freeldr/include/linux.h
@@ -127,9 +127,9 @@ typedef struct
 VOID	BootNewLinuxKernel(VOID);				// Implemented in linux.S
 VOID	BootOldLinuxKernel(ULONG KernelSize);		// Implemented in linux.S
 
-VOID	LoadAndBootLinux(PCHAR OperatingSystemName, PCHAR Description);
+VOID	LoadAndBootLinux(PCSTR OperatingSystemName, PCSTR Description);
 
-BOOL	LinuxParseIniSection(PCHAR OperatingSystemName);
+BOOL	LinuxParseIniSection(PCSTR OperatingSystemName);
 BOOL	LinuxReadBootSector(PFILE LinuxKernelFile);
 BOOL	LinuxReadSetupSector(PFILE LinuxKernelFile);
 BOOL	LinuxReadKernel(PFILE LinuxKernelFile);
diff --git a/reactos/boot/freeldr/freeldr/include/machine.h b/reactos/boot/freeldr/freeldr/include/machine.h
index 60c08dc3c2e..a1033689ab3 100644
--- a/reactos/boot/freeldr/freeldr/include/machine.h
+++ b/reactos/boot/freeldr/freeldr/include/machine.h
@@ -72,7 +72,7 @@ typedef struct tagMACHVTBL
   VOID (*HwDetect)(VOID);
 } MACHVTBL, *PMACHVTBL;
 
-VOID MachInit(char *CmdLine);
+VOID MachInit(const char *CmdLine);
 
 extern MACHVTBL MachVtbl;
 
diff --git a/reactos/boot/freeldr/freeldr/include/miscboot.h b/reactos/boot/freeldr/freeldr/include/miscboot.h
index 51eb9ed3562..e274c9ae2af 100644
--- a/reactos/boot/freeldr/freeldr/include/miscboot.h
+++ b/reactos/boot/freeldr/freeldr/include/miscboot.h
@@ -20,8 +20,8 @@
 #ifndef __BOOT_H
 #define __BOOT_H
 
-VOID	LoadAndBootBootSector(PCHAR OperatingSystemName);
-VOID	LoadAndBootPartition(PCHAR OperatingSystemName);
-VOID	LoadAndBootDrive(PCHAR OperatingSystemName);
+VOID	LoadAndBootBootSector(PCSTR OperatingSystemName);
+VOID	LoadAndBootPartition(PCSTR OperatingSystemName);
+VOID	LoadAndBootDrive(PCSTR OperatingSystemName);
 
 #endif // defined __BOOT_H
diff --git a/reactos/boot/freeldr/freeldr/include/oslist.h b/reactos/boot/freeldr/freeldr/include/oslist.h
index ea67c672e13..9996b8267bc 100644
--- a/reactos/boot/freeldr/freeldr/include/oslist.h
+++ b/reactos/boot/freeldr/freeldr/include/oslist.h
@@ -20,7 +20,7 @@
 #ifndef __OSLIST_H
 #define __OSLIST_H
 
-BOOL	InitOperatingSystemList(PCHAR **SectionNamesPointer, PCHAR **DisplayNamesPointer, ULONG* OperatingSystemCountPointer);
+BOOL	InitOperatingSystemList(PCSTR **SectionNamesPointer, PCSTR **DisplayNamesPointer, ULONG* OperatingSystemCountPointer);
 ULONG		CountOperatingSystems(ULONG SectionId);
 BOOL	AllocateListMemory(PCHAR **SectionNamesPointer, PCHAR **DisplayNamesPointer, ULONG OperatingSystemCount);
 BOOL	RemoveQuotes(PCHAR QuotedString);
diff --git a/reactos/boot/freeldr/freeldr/include/reactos.h b/reactos/boot/freeldr/freeldr/include/reactos.h
index fdb3585d4af..80de92bcbf8 100644
--- a/reactos/boot/freeldr/freeldr/include/reactos.h
+++ b/reactos/boot/freeldr/freeldr/include/reactos.h
@@ -26,7 +26,7 @@
 // ReactOS Loading Functions
 //
 ///////////////////////////////////////////////////////////////////////////////////////
-VOID LoadAndBootReactOS(PCHAR OperatingSystemName);
+VOID LoadAndBootReactOS(PCSTR OperatingSystemName);
 
 ///////////////////////////////////////////////////////////////////////////////////////
 //
@@ -61,8 +61,8 @@ VOID FASTCALL FrLdrSetupPae(ULONG Magic);
 VOID FASTCALL FrLdrSetupPageDirectory(VOID);
 VOID FASTCALL FrLdrGetPaeMode(VOID);
 BOOL STDCALL FrLdrMapKernel(FILE *KernelImage);
-ULONG_PTR STDCALL FrLdrCreateModule(LPSTR ModuleName);
-ULONG_PTR STDCALL FrLdrLoadModule(FILE *ModuleImage, LPSTR ModuleName, PULONG ModuleSize);
+ULONG_PTR STDCALL FrLdrCreateModule(LPCSTR ModuleName);
+ULONG_PTR STDCALL FrLdrLoadModule(FILE *ModuleImage, LPCSTR ModuleName, PULONG ModuleSize);
 BOOL STDCALL FrLdrCloseModule(ULONG_PTR ModuleBase, ULONG dwModuleSize);
 VOID STDCALL FrLdrStartup(ULONG Magic);
 typedef VOID (FASTCALL *ASMCODE)(ULONG Magic, PLOADER_PARAMETER_BLOCK LoaderBlock);
diff --git a/reactos/boot/freeldr/freeldr/include/rtl.h b/reactos/boot/freeldr/freeldr/include/rtl.h
index d34db55b40f..088e72d13c7 100644
--- a/reactos/boot/freeldr/freeldr/include/rtl.h
+++ b/reactos/boot/freeldr/freeldr/include/rtl.h
@@ -63,7 +63,6 @@ void	sound(int freq);
 #define min(a, b)  (((a) < (b)) ? (a) : (b))
 #endif
 
-#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
 #define UINT64_C(val) val##ULL
 
 ///////////////////////////////////////////////////////////////////////////////////////
diff --git a/reactos/boot/freeldr/freeldr/include/ui.h b/reactos/boot/freeldr/freeldr/include/ui.h
index 64b4d6aa93b..307f06830f8 100644
--- a/reactos/boot/freeldr/freeldr/include/ui.h
+++ b/reactos/boot/freeldr/freeldr/include/ui.h
@@ -47,7 +47,7 @@ extern	BOOL	UserInterfaceUp;								// Tells us if the user interface is display
 
 extern	BOOL	UiUseSpecialEffects;							// Tells us if we should use fade effects
 
-extern	CHAR	UiMonthNames[12][15];
+extern	const CHAR	UiMonthNames[12][15];
 
 ///////////////////////////////////////////////////////////////////////////////////////
 //
@@ -56,26 +56,26 @@ extern	CHAR	UiMonthNames[12][15];
 ///////////////////////////////////////////////////////////////////////////////////////
 BOOL	UiInitialize(BOOLEAN ShowGui);								// Initialize User-Interface
 BOOL	SetupUiInitialize(VOID);						// Initialize User-Interface
-VOID	UiUnInitialize(PCHAR BootText);						// Un-initialize User-Interface
+VOID	UiUnInitialize(PCSTR BootText);						// Un-initialize User-Interface
 VOID	UiDrawBackdrop(VOID);									// Fills the entire screen with a backdrop
 VOID	UiFillArea(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, CHAR FillChar, UCHAR Attr /* Color Attributes */);	// Fills the area specified with FillChar and Attr
 VOID	UiDrawShadow(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom);	// Draws a shadow on the bottom and right sides of the area specified
 VOID	UiDrawBox(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, UCHAR VertStyle, UCHAR HorzStyle, BOOL Fill, BOOL Shadow, UCHAR Attr);	// Draws a box around the area specified
-VOID	UiDrawText(ULONG X, ULONG Y, PCHAR Text, UCHAR Attr);	// Draws text at coordinates specified
-VOID	UiDrawCenteredText(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, PCHAR TextString, UCHAR Attr);	// Draws centered text at the coordinates specified and clips the edges
-VOID	UiDrawStatusText(PCHAR StatusText);					// Draws text at the very bottom line on the screen
+VOID	UiDrawText(ULONG X, ULONG Y, PCSTR Text, UCHAR Attr);	// Draws text at coordinates specified
+VOID	UiDrawCenteredText(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, PCSTR TextString, UCHAR Attr);	// Draws centered text at the coordinates specified and clips the edges
+VOID	UiDrawStatusText(PCSTR StatusText);					// Draws text at the very bottom line on the screen
 VOID	UiUpdateDateTime(VOID);									// Updates the date and time
-VOID	UiInfoBox(PCHAR MessageText);							// Displays a info box on the screen
-VOID	UiMessageBox(PCHAR MessageText);						// Displays a message box on the screen with an ok button
-VOID	UiMessageBoxCritical(PCHAR MessageText);				// Displays a message box on the screen with an ok button using no system resources
+VOID	UiInfoBox(PCSTR MessageText);							// Displays a info box on the screen
+VOID	UiMessageBox(PCSTR MessageText);						// Displays a message box on the screen with an ok button
+VOID	UiMessageBoxCritical(PCSTR MessageText);				// Displays a message box on the screen with an ok button using no system resources
 VOID	UiDrawProgressBarCenter(ULONG Position, ULONG Range, PCHAR ProgressText);			// Draws the progress bar showing nPos percent filled
 VOID	UiDrawProgressBar(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, ULONG Position, ULONG Range, PCHAR ProgressText);			// Draws the progress bar showing nPos percent filled
-VOID	UiShowMessageBoxesInSection(PCHAR SectionName);		// Displays all the message boxes in a given section
+VOID	UiShowMessageBoxesInSection(PCSTR SectionName);		// Displays all the message boxes in a given section
 VOID	UiEscapeString(PCHAR String);							// Processes a string and changes all occurances of "\n" to '\n'
-BOOL	UiEditBox(PCHAR MessageText, PCHAR EditTextBuffer, ULONG Length);
+BOOL	UiEditBox(PCSTR MessageText, PCHAR EditTextBuffer, ULONG Length);
 
-UCHAR	UiTextToColor(PCHAR ColorText);						// Converts the text color into it's equivalent color value
-UCHAR	UiTextToFillStyle(PCHAR FillStyleText);				// Converts the text fill into it's equivalent fill value
+UCHAR	UiTextToColor(PCSTR ColorText);						// Converts the text color into it's equivalent color value
+UCHAR	UiTextToFillStyle(PCSTR FillStyleText);				// Converts the text fill into it's equivalent fill value
 
 VOID	UiTruncateStringEllipsis(PCHAR StringText, ULONG MaxChars);	// Truncates a string to MaxChars by adding an ellipsis on the end '...'
 
@@ -89,7 +89,7 @@ VOID	UiFadeOut(VOID);										// Fades the screen out
 ///////////////////////////////////////////////////////////////////////////////////////
 typedef BOOL	(*UiMenuKeyPressFilterCallback)(ULONG KeyPress);
 
-BOOL	UiDisplayMenu(PCHAR MenuItemList[], ULONG MenuItemCount, ULONG DefaultMenuItem, LONG MenuTimeOut, ULONG* SelectedMenuItem, BOOL CanEscape, UiMenuKeyPressFilterCallback KeyPressFilter);
+BOOL	UiDisplayMenu(PCSTR MenuItemList[], ULONG MenuItemCount, ULONG DefaultMenuItem, LONG MenuTimeOut, ULONG* SelectedMenuItem, BOOL CanEscape, UiMenuKeyPressFilterCallback KeyPressFilter);
 
 
 
diff --git a/reactos/boot/freeldr/freeldr/inifile/inifile.c b/reactos/boot/freeldr/freeldr/inifile/inifile.c
index ab20274b1f3..ecbb8a08e5e 100644
--- a/reactos/boot/freeldr/freeldr/inifile/inifile.c
+++ b/reactos/boot/freeldr/freeldr/inifile/inifile.c
@@ -24,7 +24,7 @@
 #include <debug.h>
 #include <mm.h>
 
-BOOL IniOpenSection(PCHAR SectionName, ULONG* SectionId)
+BOOL IniOpenSection(PCSTR SectionName, ULONG* SectionId)
 {
 	PINI_SECTION	Section;
 
@@ -131,7 +131,7 @@ BOOL IniReadSettingByNumber(ULONG SectionId, ULONG SettingNumber, PCHAR SettingN
 	return FALSE;
 }
 
-BOOL IniReadSettingByName(ULONG SectionId, PCHAR SettingName, PCHAR Buffer, ULONG BufferSize)
+BOOL IniReadSettingByName(ULONG SectionId, PCSTR SettingName, PCHAR Buffer, ULONG BufferSize)
 {
 	PINI_SECTION		Section = (PINI_SECTION)SectionId;
 	PINI_SECTION_ITEM	SectionItem;
@@ -163,7 +163,7 @@ BOOL IniReadSettingByName(ULONG SectionId, PCHAR SettingName, PCHAR Buffer, ULON
 	return FALSE;
 }
 
-BOOL IniAddSection(PCHAR SectionName, ULONG* SectionId)
+BOOL IniAddSection(PCSTR SectionName, ULONG* SectionId)
 {
 	PINI_SECTION	Section;
 
@@ -203,7 +203,7 @@ BOOL IniAddSection(PCHAR SectionName, ULONG* SectionId)
 	return TRUE;
 }
 
-BOOL IniAddSettingValueToSection(ULONG SectionId, PCHAR SettingName, PCHAR SettingValue)
+BOOL IniAddSettingValueToSection(ULONG SectionId, PCSTR SettingName, PCSTR SettingValue)
 {
 	PINI_SECTION		Section = (PINI_SECTION)SectionId;
 	PINI_SECTION_ITEM	SectionItem;
diff --git a/reactos/boot/freeldr/freeldr/linuxboot.c b/reactos/boot/freeldr/freeldr/linuxboot.c
index e2bc48d70ec..d98e9166c58 100644
--- a/reactos/boot/freeldr/freeldr/linuxboot.c
+++ b/reactos/boot/freeldr/freeldr/linuxboot.c
@@ -54,7 +54,7 @@ PVOID			LinuxInitrdLoadAddress = NULL;
 CHAR			LinuxBootDescription[80];
 CHAR			LinuxBootPath[260] = "";
 
-VOID LoadAndBootLinux(PCHAR OperatingSystemName, PCHAR Description)
+VOID LoadAndBootLinux(PCSTR OperatingSystemName, PCSTR Description)
 {
 	PFILE	LinuxKernel = NULL;
 	PFILE	LinuxInitrdFile = NULL;
@@ -229,7 +229,7 @@ LinuxBootFailed:
 	LinuxCommandLineSize = 0;
 }
 
-BOOL LinuxParseIniSection(PCHAR OperatingSystemName)
+BOOL LinuxParseIniSection(PCSTR OperatingSystemName)
 {
 	CHAR	SettingName[260];
 	ULONG	SectionId;
diff --git a/reactos/boot/freeldr/freeldr/miscboot.c b/reactos/boot/freeldr/freeldr/miscboot.c
index ff2cfe6b29f..5a45bfa154c 100644
--- a/reactos/boot/freeldr/freeldr/miscboot.c
+++ b/reactos/boot/freeldr/freeldr/miscboot.c
@@ -29,7 +29,7 @@
 #include <drivemap.h>
 #include <machine.h>
 
-VOID LoadAndBootBootSector(PCHAR OperatingSystemName)
+VOID LoadAndBootBootSector(PCSTR OperatingSystemName)
 {
 	PFILE	FilePointer;
 	CHAR	SettingName[80];
@@ -100,7 +100,7 @@ VOID LoadAndBootBootSector(PCHAR OperatingSystemName)
 	ChainLoadBiosBootSectorCode();
 }
 
-VOID LoadAndBootPartition(PCHAR OperatingSystemName)
+VOID LoadAndBootPartition(PCSTR OperatingSystemName)
 {
 	CHAR			SettingName[80];
 	CHAR			SettingValue[80];
@@ -171,7 +171,7 @@ VOID LoadAndBootPartition(PCHAR OperatingSystemName)
 	ChainLoadBiosBootSectorCode();
 }
 
-VOID LoadAndBootDrive(PCHAR OperatingSystemName)
+VOID LoadAndBootDrive(PCSTR OperatingSystemName)
 {
 	CHAR	SettingName[80];
 	CHAR	SettingValue[80];
diff --git a/reactos/boot/freeldr/freeldr/options.c b/reactos/boot/freeldr/freeldr/options.c
index c07144c020c..31d9e57ea08 100644
--- a/reactos/boot/freeldr/freeldr/options.c
+++ b/reactos/boot/freeldr/freeldr/options.c
@@ -27,7 +27,7 @@
 #include <arch.h>
 
 
-PCHAR	OptionsMenuList[] =
+PCSTR	OptionsMenuList[] =
 {
 	"Safe Mode",
 	"Safe Mode with Networking",
diff --git a/reactos/boot/freeldr/freeldr/oslist.c b/reactos/boot/freeldr/freeldr/oslist.c
index eb4fe24200f..fb001f53c73 100644
--- a/reactos/boot/freeldr/freeldr/oslist.c
+++ b/reactos/boot/freeldr/freeldr/oslist.c
@@ -24,7 +24,7 @@
 #include <mm.h>
 #include <ui.h>
 
-BOOL InitOperatingSystemList(PCHAR **SectionNamesPointer, PCHAR **DisplayNamesPointer, ULONG* OperatingSystemCountPointer)
+BOOL InitOperatingSystemList(PCSTR **SectionNamesPointer, PCSTR **DisplayNamesPointer, ULONG* OperatingSystemCountPointer)
 {
 	ULONG		Idx;
 	ULONG		CurrentOperatingSystemIndex;
@@ -79,8 +79,8 @@ BOOL InitOperatingSystemList(PCHAR **SectionNamesPointer, PCHAR **DisplayNamesPo
 	}
 
 	*OperatingSystemCountPointer = OperatingSystemCount;
-	*SectionNamesPointer = OperatingSystemSectionNames;
-	*DisplayNamesPointer = OperatingSystemDisplayNames;
+	*SectionNamesPointer = (PCSTR*)OperatingSystemSectionNames;
+	*DisplayNamesPointer = (PCSTR*)OperatingSystemDisplayNames;
 
 	return TRUE;
 }
diff --git a/reactos/boot/freeldr/freeldr/reactos/binhive.c b/reactos/boot/freeldr/freeldr/reactos/binhive.c
index 2fa61c9a156..8c3edb61c85 100644
--- a/reactos/boot/freeldr/freeldr/reactos/binhive.c
+++ b/reactos/boot/freeldr/freeldr/reactos/binhive.c
@@ -326,7 +326,7 @@ CmiCreateDefaultBinCell (PHBIN BinCell)
 
 
 static VOID
-CmiCreateDefaultRootKeyCell (PKEY_CELL RootKeyCell, PCHAR KeyName)
+CmiCreateDefaultRootKeyCell (PKEY_CELL RootKeyCell, PCSTR KeyName)
 {
   PCHAR BaseKeyName;
   ULONG NameSize;
@@ -357,7 +357,7 @@ CmiCreateDefaultRootKeyCell (PKEY_CELL RootKeyCell, PCHAR KeyName)
 
 
 static PREGISTRY_HIVE
-CmiCreateHive (PCHAR KeyName)
+CmiCreateHive (PCSTR KeyName)
 {
   PREGISTRY_HIVE Hive;
   PCELL_HEADER FreeCell;
@@ -1258,7 +1258,7 @@ CmiCalcHiveChecksum (PREGISTRY_HIVE Hive)
 
 static BOOL
 CmiExportHive (PREGISTRY_HIVE Hive,
-	       PCHAR KeyName)
+	       PCSTR KeyName)
 {
   PKEY_CELL KeyCell;
   FRLDRHKEY Key;
@@ -1624,7 +1624,7 @@ RegImportBinaryHive(PCHAR ChunkBase,
 
 
 BOOL
-RegExportBinaryHive(PCHAR KeyName,
+RegExportBinaryHive(PCSTR KeyName,
 		    PCHAR ChunkBase,
 		    ULONG* ChunkSize)
 {
diff --git a/reactos/boot/freeldr/freeldr/reactos/loader.c b/reactos/boot/freeldr/freeldr/reactos/loader.c
index 79b7ecb7b91..9ba450e9eca 100644
--- a/reactos/boot/freeldr/freeldr/reactos/loader.c
+++ b/reactos/boot/freeldr/freeldr/reactos/loader.c
@@ -706,7 +706,7 @@ FrLdrMapKernel(FILE *KernelImage)
 ULONG_PTR
 STDCALL
 FrLdrLoadModule(FILE *ModuleImage,
-                LPSTR ModuleName,
+                LPCSTR ModuleName,
                 PULONG ModuleSize)
 {
     ULONG LocalModuleSize;
@@ -757,7 +757,7 @@ FrLdrLoadModule(FILE *ModuleImage,
 
 ULONG_PTR
 STDCALL
-FrLdrCreateModule(LPSTR ModuleName)
+FrLdrCreateModule(LPCSTR ModuleName)
 {
     PLOADER_MODULE ModuleData;
     LPSTR NameBuffer;
diff --git a/reactos/boot/freeldr/freeldr/reactos/reactos.c b/reactos/boot/freeldr/freeldr/reactos/reactos.c
index f3c37d82692..2ced6268452 100644
--- a/reactos/boot/freeldr/freeldr/reactos/reactos.c
+++ b/reactos/boot/freeldr/freeldr/reactos/reactos.c
@@ -78,7 +78,7 @@ FrLdrLoadKernel(PCHAR szFileName,
     FrLdrMapKernel(FilePointer);
 
     /* Update Processbar and return success */
-    UiDrawProgressBarCenter(nPos, 100, "Loading ReactOS...");
+    UiDrawProgressBarCenter(nPos, 100, (PCHAR)"Loading ReactOS...");
     return(TRUE);
 }
 
@@ -145,8 +145,8 @@ LoadKernelSymbols(PCHAR szKernelName, int nPos)
 }
 
 static BOOL
-FrLdrLoadNlsFile(PCHAR szFileName,
-                 PCHAR szModuleName)
+FrLdrLoadNlsFile(PCSTR szFileName,
+                 PCSTR szModuleName)
 {
     PFILE FilePointer;
     CHAR value[256];
@@ -340,7 +340,7 @@ FrLdrLoadDriver(PCHAR szFileName,
     FrLdrLoadModule(FilePointer, szFileName, NULL);
 
     /* Update status and return */
-    UiDrawProgressBarCenter(nPos, 100, "Loading ReactOS...");
+    UiDrawProgressBarCenter(nPos, 100, (PCHAR)"Loading ReactOS...");
     return(TRUE);
 }
 
@@ -570,7 +570,7 @@ FrLdrLoadBootDrivers(PCHAR szSystemRoot,
 }
 
 VOID
-LoadAndBootReactOS(PCHAR OperatingSystemName)
+LoadAndBootReactOS(PCSTR OperatingSystemName)
 {
 	PFILE FilePointer;
 	CHAR  name[1024];
@@ -704,7 +704,7 @@ LoadAndBootReactOS(PCHAR OperatingSystemName)
 	if (AcpiPresent) LoaderBlock.Flags |= MB_FLAGS_ACPI_TABLE;
 
 	UiDrawStatusText("Loading...");
-	UiDrawProgressBarCenter(0, 100, "Loading ReactOS...");
+	UiDrawProgressBarCenter(0, 100, (PCHAR)"Loading ReactOS...");
 
 	/*
 	 * Try to open system drive
@@ -838,7 +838,7 @@ LoadAndBootReactOS(PCHAR OperatingSystemName)
 	 */
 	RegInitCurrentControlSet(FALSE);
 
-	UiDrawProgressBarCenter(15, 100, "Loading ReactOS...");
+	UiDrawProgressBarCenter(15, 100, (PCHAR)"Loading ReactOS...");
 
 	/*
 	 * Export the hardware hive
@@ -847,7 +847,7 @@ LoadAndBootReactOS(PCHAR OperatingSystemName)
 	RegExportBinaryHive ("\\Registry\\Machine\\HARDWARE", (PCHAR)Base, &Size);
 	FrLdrCloseModule (Base, Size);
 
-	UiDrawProgressBarCenter(20, 100, "Loading ReactOS...");
+	UiDrawProgressBarCenter(20, 100, (PCHAR)"Loading ReactOS...");
 
 	/*
 	 * Load NLS files
@@ -857,13 +857,13 @@ LoadAndBootReactOS(PCHAR OperatingSystemName)
 	        UiMessageBox(MsgBuffer);
 		return;
 	}
-	UiDrawProgressBarCenter(30, 100, "Loading ReactOS...");
+	UiDrawProgressBarCenter(30, 100, (PCHAR)"Loading ReactOS...");
 
 	/*
 	 * Load kernel symbols
 	 */
 	LoadKernelSymbols(szKernelName, 30);
-	UiDrawProgressBarCenter(40, 100, "Loading ReactOS...");
+	UiDrawProgressBarCenter(40, 100, (PCHAR)"Loading ReactOS...");
 
 	/*
 	 * Load boot drivers
diff --git a/reactos/boot/freeldr/freeldr/reactos/registry.c b/reactos/boot/freeldr/freeldr/reactos/registry.c
index b488ff2fed7..c00ae732c5e 100644
--- a/reactos/boot/freeldr/freeldr/reactos/registry.c
+++ b/reactos/boot/freeldr/freeldr/reactos/registry.c
@@ -206,7 +206,7 @@ RegInitCurrentControlSet(BOOL LastKnownGood)
 
 LONG
 RegCreateKey(FRLDRHKEY ParentKey,
-	     PCHAR KeyName,
+	     PCSTR KeyName,
 	     PFRLDRHKEY Key)
 {
   PLIST_ENTRY Ptr;
@@ -214,7 +214,7 @@ RegCreateKey(FRLDRHKEY ParentKey,
   FRLDRHKEY CurrentKey;
   FRLDRHKEY NewKey;
   PCHAR p;
-  PCHAR name;
+  PCSTR name;
   int subkeyLength;
   int stringLength;
 
@@ -331,7 +331,7 @@ RegCreateKey(FRLDRHKEY ParentKey,
 
 LONG
 RegDeleteKey(FRLDRHKEY Key,
-	     PCHAR Name)
+	     PCSTR Name)
 {
 
 
@@ -384,14 +384,14 @@ RegEnumKey(FRLDRHKEY Key,
 
 LONG
 RegOpenKey(FRLDRHKEY ParentKey,
-	   PCHAR KeyName,
+	   PCSTR KeyName,
 	   PFRLDRHKEY Key)
 {
   PLIST_ENTRY Ptr;
   FRLDRHKEY SearchKey = NULL;
   FRLDRHKEY CurrentKey;
   PCHAR p;
-  PCHAR name;
+  PCSTR name;
   int subkeyLength;
   int stringLength;
 
@@ -484,9 +484,9 @@ RegOpenKey(FRLDRHKEY ParentKey,
 
 LONG
 RegSetValue(FRLDRHKEY Key,
-	    PCHAR ValueName,
+	    PCSTR ValueName,
 	    ULONG Type,
-	    PCHAR Data,
+	    PCSTR Data,
 	    ULONG DataSize)
 {
   PLIST_ENTRY Ptr;
@@ -585,7 +585,7 @@ RegSetValue(FRLDRHKEY Key,
 
 LONG
 RegQueryValue(FRLDRHKEY Key,
-	      PCHAR ValueName,
+	      PCSTR ValueName,
 	      ULONG* Type,
 	      PUCHAR Data,
 	      ULONG* DataSize)
@@ -672,7 +672,7 @@ RegQueryValue(FRLDRHKEY Key,
 
 LONG
 RegDeleteValue(FRLDRHKEY Key,
-	       PCHAR ValueName)
+	       PCSTR ValueName)
 {
   PLIST_ENTRY Ptr;
   PVALUE Value = NULL;
diff --git a/reactos/boot/freeldr/freeldr/reactos/registry.h b/reactos/boot/freeldr/freeldr/reactos/registry.h
index b5b9493ce88..e2894f0d9dc 100644
--- a/reactos/boot/freeldr/freeldr/reactos/registry.h
+++ b/reactos/boot/freeldr/freeldr/reactos/registry.h
@@ -72,12 +72,12 @@ RegInitCurrentControlSet(BOOL LastKnownGood);
 
 LONG
 RegCreateKey(FRLDRHKEY ParentKey,
-	     PCHAR KeyName,
+	     PCSTR KeyName,
 	     PFRLDRHKEY Key);
 
 LONG
 RegDeleteKey(FRLDRHKEY Key,
-	     PCHAR Name);
+	     PCSTR Name);
 
 LONG
 RegEnumKey(FRLDRHKEY Key,
@@ -87,27 +87,27 @@ RegEnumKey(FRLDRHKEY Key,
 
 LONG
 RegOpenKey(FRLDRHKEY ParentKey,
-	   PCHAR KeyName,
+	   PCSTR KeyName,
 	   PFRLDRHKEY Key);
 
 
 LONG
 RegSetValue(FRLDRHKEY Key,
-	    PCHAR ValueName,
+	    PCSTR ValueName,
 	    ULONG Type,
-	    PCHAR Data,
+	    PCSTR Data,
 	    ULONG DataSize);
 
 LONG
 RegQueryValue(FRLDRHKEY Key,
-	      PCHAR ValueName,
+	      PCSTR ValueName,
 	      ULONG* Type,
 	      PUCHAR Data,
 	      ULONG* DataSize);
 
 LONG
 RegDeleteValue(FRLDRHKEY Key,
-	       PCHAR ValueName);
+	       PCSTR ValueName);
 
 LONG
 RegEnumValue(FRLDRHKEY Key,
@@ -130,7 +130,7 @@ RegImportBinaryHive (PCHAR ChunkBase,
 		     ULONG ChunkSize);
 
 BOOL
-RegExportBinaryHive (PCHAR KeyName,
+RegExportBinaryHive (PCSTR KeyName,
 		     PCHAR ChunkBase,
 		     ULONG* ChunkSize);
 
diff --git a/reactos/boot/freeldr/freeldr/ui/gui.c b/reactos/boot/freeldr/freeldr/ui/gui.c
index 36e050c54cc..2339ce94671 100644
--- a/reactos/boot/freeldr/freeldr/ui/gui.c
+++ b/reactos/boot/freeldr/freeldr/ui/gui.c
@@ -46,7 +46,7 @@ VOID GuiDrawText(ULONG X, ULONG Y, PUCHAR Text, UCHAR Attr)
 {
 }
 
-VOID GuiDrawStatusText(PUCHAR StatusText)
+VOID GuiDrawStatusText(PCSTR StatusText)
 {
 }
 
@@ -62,11 +62,11 @@ VOID GuiRestoreScreen(PUCHAR Buffer)
 {
 }
 
-VOID GuiMessageBox(PUCHAR MessageText)
+VOID GuiMessageBox(PCSTR MessageText)
 {
 }
 
-VOID GuiMessageBoxCritical(PUCHAR MessageText)
+VOID GuiMessageBoxCritical(PCSTR MessageText)
 {
 }
 
@@ -74,12 +74,12 @@ VOID GuiDrawProgressBar(ULONG Position, ULONG Range)
 {
 }
 
-UCHAR GuiTextToColor(PUCHAR ColorText)
+UCHAR GuiTextToColor(PCSTR ColorText)
 {
 	return 0;
 }
 
-UCHAR GuiTextToFillStyle(PUCHAR FillStyleText)
+UCHAR GuiTextToFillStyle(PCSTR FillStyleText)
 {
 	return 0;
 }
diff --git a/reactos/boot/freeldr/freeldr/ui/gui.h b/reactos/boot/freeldr/freeldr/ui/gui.h
index ad1e031440f..0b431488ebc 100644
--- a/reactos/boot/freeldr/freeldr/ui/gui.h
+++ b/reactos/boot/freeldr/freeldr/ui/gui.h
@@ -33,23 +33,23 @@ VOID	GuiFillArea(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, UCHAR FillCha
 VOID	GuiDrawShadow(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom);	// Draws a shadow on the bottom and right sides of the area specified
 VOID	GuiDrawBox(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, UCHAR VertStyle, UCHAR HorzStyle, BOOL Fill, BOOL Shadow, UCHAR Attr);	// Draws a box around the area specified
 VOID	GuiDrawText(ULONG X, ULONG Y, PUCHAR Text, UCHAR Attr);	// Draws text at coordinates specified
-VOID	GuiDrawStatusText(PUCHAR StatusText);					// Draws text at the very bottom line on the screen
+VOID	GuiDrawStatusText(PCSTR StatusText);					// Draws text at the very bottom line on the screen
 VOID	GuiUpdateDateTime(VOID);								// Updates the date and time
 VOID	GuiSaveScreen(PUCHAR Buffer);							// Saves the screen so that it can be restored later
 VOID	GuiRestoreScreen(PUCHAR Buffer);						// Restores the screen from a previous save
-VOID	GuiMessageBox(PUCHAR MessageText);						// Displays a message box on the screen with an ok button
-VOID	GuiMessageBoxCritical(PUCHAR MessageText);				// Displays a message box on the screen with an ok button using no system resources
+VOID	GuiMessageBox(PCSTR MessageText);						// Displays a message box on the screen with an ok button
+VOID	GuiMessageBoxCritical(PCSTR MessageText);				// Displays a message box on the screen with an ok button using no system resources
 VOID	GuiDrawProgressBar(ULONG Position, ULONG Range);		// Draws the progress bar showing nPos percent filled
 
-UCHAR	GuiTextToColor(PUCHAR ColorText);						// Converts the text color into it's equivalent color value
-UCHAR	GuiTextToFillStyle(PUCHAR FillStyleText);				// Converts the text fill into it's equivalent fill value
+UCHAR	GuiTextToColor(PCSTR ColorText);						// Converts the text color into it's equivalent color value
+UCHAR	GuiTextToFillStyle(PCSTR FillStyleText);				// Converts the text fill into it's equivalent fill value
 
 ///////////////////////////////////////////////////////////////////////////////////////
 //
 // Menu Functions
 //
 ///////////////////////////////////////////////////////////////////////////////////////
-BOOL	GuiDisplayMenu(PUCHAR MenuItemList[], ULONG MenuItemCount, ULONG DefaultMenuItem, LONG MenuTimeOut, ULONG* SelectedMenuItem);
+BOOL	GuiDisplayMenu(PCSTR MenuItemList[], ULONG MenuItemCount, ULONG DefaultMenuItem, LONG MenuTimeOut, ULONG* SelectedMenuItem);
 
 
 
diff --git a/reactos/boot/freeldr/freeldr/ui/tui.c b/reactos/boot/freeldr/freeldr/ui/tui.c
index 6cd5397a79e..3c0874adb2d 100644
--- a/reactos/boot/freeldr/freeldr/ui/tui.c
+++ b/reactos/boot/freeldr/freeldr/ui/tui.c
@@ -304,7 +304,7 @@ VOID TuiDrawBox(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, UCHAR VertStyl
  * DrawText()
  * This function assumes coordinates are zero-based
  */
-VOID TuiDrawText(ULONG X, ULONG Y, PCHAR Text, UCHAR Attr)
+VOID TuiDrawText(ULONG X, ULONG Y, PCSTR Text, UCHAR Attr)
 {
 	PUCHAR	ScreenMemory = (PUCHAR)TextVideoBuffer;
 	ULONG		i, j;
@@ -317,7 +317,7 @@ VOID TuiDrawText(ULONG X, ULONG Y, PCHAR Text, UCHAR Attr)
 	}
 }
 
-VOID TuiDrawCenteredText(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, PCHAR TextString, UCHAR Attr)
+VOID TuiDrawCenteredText(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, PCSTR TextString, UCHAR Attr)
 {
 	ULONG		TextLength;
 	ULONG		BoxWidth;
@@ -378,7 +378,7 @@ VOID TuiDrawCenteredText(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, PCHAR
 	}
 }
 
-VOID TuiDrawStatusText(PCHAR StatusText)
+VOID TuiDrawStatusText(PCSTR StatusText)
 {
 	ULONG		i;
 
@@ -504,7 +504,7 @@ VOID TuiRestoreScreen(PUCHAR Buffer)
 	}
 }
 
-VOID TuiMessageBox(PCHAR MessageText)
+VOID TuiMessageBox(PCSTR MessageText)
 {
 	PVOID	ScreenBuffer;
 
@@ -520,7 +520,7 @@ VOID TuiMessageBox(PCHAR MessageText)
 	MmFreeMemory(ScreenBuffer);
 }
 
-VOID TuiMessageBoxCritical(PCHAR MessageText)
+VOID TuiMessageBoxCritical(PCSTR MessageText)
 {
 	int		width = 8;
 	unsigned int	height = 1;
@@ -662,7 +662,7 @@ VOID TuiDrawProgressBar(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, ULONG
 	VideoCopyOffScreenBufferToVRAM();
 }
 
-UCHAR TuiTextToColor(PCHAR ColorText)
+UCHAR TuiTextToColor(PCSTR ColorText)
 {
 	if (stricmp(ColorText, "Black") == 0)
 		return COLOR_BLACK;
@@ -700,7 +700,7 @@ UCHAR TuiTextToColor(PCHAR ColorText)
 	return COLOR_BLACK;
 }
 
-UCHAR TuiTextToFillStyle(PCHAR FillStyleText)
+UCHAR TuiTextToFillStyle(PCSTR FillStyleText)
 {
 	if (stricmp(FillStyleText, "Light") == 0)
 	{
@@ -772,7 +772,7 @@ VOID TuiFadeOut(VOID)
 
 }
 
-BOOL TuiEditBox(PCHAR MessageText, PCHAR EditTextBuffer, ULONG Length)
+BOOL TuiEditBox(PCSTR MessageText, PCHAR EditTextBuffer, ULONG Length)
 {
 	int		width = 8;
 	unsigned int	height = 1;
diff --git a/reactos/boot/freeldr/freeldr/ui/tui.h b/reactos/boot/freeldr/freeldr/ui/tui.h
index 09d61eb65e2..c014930100e 100644
--- a/reactos/boot/freeldr/freeldr/ui/tui.h
+++ b/reactos/boot/freeldr/freeldr/ui/tui.h
@@ -35,20 +35,20 @@ VOID	TuiDrawBackdrop(VOID);									// Fills the entire screen with a backdrop
 VOID	TuiFillArea(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, CHAR FillChar, UCHAR Attr /* Color Attributes */);	// Fills the area specified with FillChar and Attr
 VOID	TuiDrawShadow(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom);	// Draws a shadow on the bottom and right sides of the area specified
 VOID	TuiDrawBox(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, UCHAR VertStyle, UCHAR HorzStyle, BOOL Fill, BOOL Shadow, UCHAR Attr);	// Draws a box around the area specified
-VOID	TuiDrawText(ULONG X, ULONG Y, PCHAR Text, UCHAR Attr);	// Draws text at coordinates specified
-VOID	TuiDrawCenteredText(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, PCHAR TextString, UCHAR Attr);	// Draws centered text at the coordinates specified and clips the edges
-VOID	TuiDrawStatusText(PCHAR StatusText);					// Draws text at the very bottom line on the screen
+VOID	TuiDrawText(ULONG X, ULONG Y, PCSTR Text, UCHAR Attr);	// Draws text at coordinates specified
+VOID	TuiDrawCenteredText(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, PCSTR TextString, UCHAR Attr);	// Draws centered text at the coordinates specified and clips the edges
+VOID	TuiDrawStatusText(PCSTR StatusText);					// Draws text at the very bottom line on the screen
 VOID	TuiUpdateDateTime(VOID);								// Updates the date and time
 VOID	TuiSaveScreen(PUCHAR Buffer);							// Saves the screen so that it can be restored later
 VOID	TuiRestoreScreen(PUCHAR Buffer);						// Restores the screen from a previous save
-VOID	TuiMessageBox(PCHAR MessageText);						// Displays a message box on the screen with an ok button
-VOID	TuiMessageBoxCritical(PCHAR MessageText);				// Displays a message box on the screen with an ok button using no system resources
+VOID	TuiMessageBox(PCSTR MessageText);						// Displays a message box on the screen with an ok button
+VOID	TuiMessageBoxCritical(PCSTR MessageText);				// Displays a message box on the screen with an ok button using no system resources
 VOID	TuiDrawProgressBarCenter(ULONG Position, ULONG Range, PCHAR ProgressText);			// Draws the progress bar showing nPos percent filled
 VOID	TuiDrawProgressBar(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, ULONG Position, ULONG Range, PCHAR ProgressText);			// Draws the progress bar showing nPos percent filled
-BOOL	TuiEditBox(PCHAR MessageText, PCHAR EditTextBuffer, ULONG Length);
+BOOL	TuiEditBox(PCSTR MessageText, PCHAR EditTextBuffer, ULONG Length);
 
-UCHAR	TuiTextToColor(PCHAR ColorText);						// Converts the text color into it's equivalent color value
-UCHAR	TuiTextToFillStyle(PCHAR FillStyleText);				// Converts the text fill into it's equivalent fill value
+UCHAR	TuiTextToColor(PCSTR ColorText);						// Converts the text color into it's equivalent color value
+UCHAR	TuiTextToFillStyle(PCSTR FillStyleText);				// Converts the text fill into it's equivalent fill value
 
 VOID	TuiFadeInBackdrop(VOID);								// Draws the backdrop and fades the screen in
 VOID	TuiFadeOut(VOID);										// Fades the screen out
@@ -61,7 +61,7 @@ VOID	TuiFadeOut(VOID);										// Fades the screen out
 
 typedef struct
 {
-	PCHAR		*MenuItemList;
+	PCSTR		*MenuItemList;
 	ULONG		MenuItemCount;
 	LONG		MenuTimeRemaining;
 	ULONG		SelectedMenuItem;
@@ -78,7 +78,7 @@ VOID	TuiDrawMenu(PTUI_MENU_INFO MenuInfo);
 VOID	TuiDrawMenuBox(PTUI_MENU_INFO MenuInfo);
 VOID	TuiDrawMenuItem(PTUI_MENU_INFO MenuInfo, ULONG MenuItemNumber);
 ULONG		TuiProcessMenuKeyboardEvent(PTUI_MENU_INFO MenuInfo, UiMenuKeyPressFilterCallback KeyPressFilter);
-BOOL	TuiDisplayMenu(PCHAR MenuItemList[], ULONG MenuItemCount, ULONG DefaultMenuItem, LONG MenuTimeOut, ULONG* SelectedMenuItem, BOOL CanEscape, UiMenuKeyPressFilterCallback KeyPressFilter);
+BOOL	TuiDisplayMenu(PCSTR MenuItemList[], ULONG MenuItemCount, ULONG DefaultMenuItem, LONG MenuTimeOut, ULONG* SelectedMenuItem, BOOL CanEscape, UiMenuKeyPressFilterCallback KeyPressFilter);
 
 
 /*
diff --git a/reactos/boot/freeldr/freeldr/ui/tuimenu.c b/reactos/boot/freeldr/freeldr/ui/tuimenu.c
index 7a26126b869..923612da3dd 100644
--- a/reactos/boot/freeldr/freeldr/ui/tuimenu.c
+++ b/reactos/boot/freeldr/freeldr/ui/tuimenu.c
@@ -28,7 +28,7 @@
 #include <video.h>
 
 
-BOOL TuiDisplayMenu(PCHAR MenuItemList[], ULONG MenuItemCount, ULONG DefaultMenuItem, LONG MenuTimeOut, ULONG* SelectedMenuItem, BOOL CanEscape, UiMenuKeyPressFilterCallback KeyPressFilter)
+BOOL TuiDisplayMenu(PCSTR MenuItemList[], ULONG MenuItemCount, ULONG DefaultMenuItem, LONG MenuTimeOut, ULONG* SelectedMenuItem, BOOL CanEscape, UiMenuKeyPressFilterCallback KeyPressFilter)
 {
 	TUI_MENU_INFO	MenuInformation;
 	ULONG		LastClockSecond;
diff --git a/reactos/boot/freeldr/freeldr/ui/ui.c b/reactos/boot/freeldr/freeldr/ui/ui.c
index 8e976135e8b..f2056c6ae0f 100644
--- a/reactos/boot/freeldr/freeldr/ui/ui.c
+++ b/reactos/boot/freeldr/freeldr/ui/ui.c
@@ -57,7 +57,7 @@ VIDEODISPLAYMODE	UiDisplayMode		= VideoTextMode;		// Tells us if we are in text
 
 BOOL	UiUseSpecialEffects			= FALSE;				// Tells us if we should use fade effects
 
-CHAR	UiMonthNames[12][15] = { "January ", "February ", "March ", "April ", "May ", "June ", "July ", "August ", "September ", "October ", "November ", "December " };
+const CHAR	UiMonthNames[12][15] = { "January ", "February ", "March ", "April ", "May ", "June ", "July ", "August ", "September ", "October ", "November ", "December " };
 
 
 BOOL UiInitialize(BOOLEAN ShowGui)
@@ -235,7 +235,7 @@ BOOL SetupUiInitialize(VOID)
 	return TRUE;
 }
 
-VOID UiUnInitialize(PCHAR BootText)
+VOID UiUnInitialize(PCSTR BootText)
 {
 	UiDrawBackdrop();
 	UiDrawStatusText("Booting...");
@@ -306,7 +306,7 @@ VOID UiDrawBox(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, UCHAR VertStyle
 	}
 }
 
-VOID UiDrawText(ULONG X, ULONG Y, PCHAR Text, UCHAR Attr)
+VOID UiDrawText(ULONG X, ULONG Y, PCSTR Text, UCHAR Attr)
 {
 	if (VideoTextMode == UiDisplayMode)
 	{
@@ -319,7 +319,7 @@ VOID UiDrawText(ULONG X, ULONG Y, PCHAR Text, UCHAR Attr)
 	}
 }
 
-VOID UiDrawCenteredText(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, PCHAR TextString, UCHAR Attr)
+VOID UiDrawCenteredText(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, PCSTR TextString, UCHAR Attr)
 {
 	if (VideoTextMode == UiDisplayMode)
 	{
@@ -332,7 +332,7 @@ VOID UiDrawCenteredText(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, PCHAR
 	}
 }
 
-VOID UiDrawStatusText(PCHAR StatusText)
+VOID UiDrawStatusText(PCSTR StatusText)
 {
 	if (!UserInterfaceUp) return;
 
@@ -360,7 +360,7 @@ VOID UiUpdateDateTime(VOID)
 	}
 }
 
-VOID UiInfoBox(PCHAR MessageText)
+VOID UiInfoBox(PCSTR MessageText)
 {
 	ULONG		TextLength;
 	ULONG		BoxWidth;
@@ -421,7 +421,7 @@ VOID UiInfoBox(PCHAR MessageText)
 	UiDrawCenteredText(Left, Top, Right, Bottom, MessageText, ATTR(UiTextColor, UiMenuBgColor));
 }
 
-VOID UiMessageBox(PCHAR MessageText)
+VOID UiMessageBox(PCSTR MessageText)
 {
 	// We have not yet displayed the user interface
 	// We are probably still reading the .ini file
@@ -446,7 +446,7 @@ VOID UiMessageBox(PCHAR MessageText)
 	}
 }
 
-VOID UiMessageBoxCritical(PCHAR MessageText)
+VOID UiMessageBoxCritical(PCSTR MessageText)
 {
 	// We have not yet displayed the user interface
 	// We are probably still reading the .ini file
@@ -471,7 +471,7 @@ VOID UiMessageBoxCritical(PCHAR MessageText)
 	}
 }
 
-UCHAR UiTextToColor(PCHAR ColorText)
+UCHAR UiTextToColor(PCSTR ColorText)
 {
 	if (VideoTextMode == UiDisplayMode)
 	{
@@ -485,7 +485,7 @@ UCHAR UiTextToColor(PCHAR ColorText)
 	}
 }
 
-UCHAR UiTextToFillStyle(PCHAR FillStyleText)
+UCHAR UiTextToFillStyle(PCSTR FillStyleText)
 {
 	if (VideoTextMode == UiDisplayMode)
 	{
@@ -527,7 +527,7 @@ VOID UiDrawProgressBar(ULONG Left, ULONG Top, ULONG Right, ULONG Bottom, ULONG P
 	}
 }
 
-VOID UiShowMessageBoxesInSection(PCHAR SectionName)
+VOID UiShowMessageBoxesInSection(PCSTR SectionName)
 {
 	ULONG		Idx;
 	CHAR	SettingName[80];
@@ -605,7 +605,7 @@ VOID UiTruncateStringEllipsis(PCHAR StringText, ULONG MaxChars)
 	}
 }
 
-BOOL UiDisplayMenu(PCHAR MenuItemList[], ULONG MenuItemCount, ULONG DefaultMenuItem, LONG MenuTimeOut, ULONG* SelectedMenuItem, BOOL CanEscape, UiMenuKeyPressFilterCallback KeyPressFilter)
+BOOL UiDisplayMenu(PCSTR MenuItemList[], ULONG MenuItemCount, ULONG DefaultMenuItem, LONG MenuTimeOut, ULONG* SelectedMenuItem, BOOL CanEscape, UiMenuKeyPressFilterCallback KeyPressFilter)
 {
 	if (VideoTextMode == UiDisplayMode)
 	{
@@ -645,7 +645,7 @@ VOID UiFadeOut(VOID)
 	}
 }
 
-BOOL UiEditBox(PCHAR MessageText, PCHAR EditTextBuffer, ULONG Length)
+BOOL UiEditBox(PCSTR MessageText, PCHAR EditTextBuffer, ULONG Length)
 {
 	if (VideoTextMode == UiDisplayMode)
 	{