diff --git a/reactos/lib/fslib/vfatlib/fat12.c b/reactos/lib/fslib/vfatlib/fat12.c
index 679e614611d..ca699f25d2e 100644
--- a/reactos/lib/fslib/vfatlib/fat12.c
+++ b/reactos/lib/fslib/vfatlib/fat12.c
@@ -272,7 +272,7 @@ Fat12Format (HANDLE  FileHandle,
 	     PFMIFSCALLBACK  Callback)
 {
   FAT16_BOOT_SECTOR BootSector;
-  ANSI_STRING VolumeLabel;
+  OEM_STRING VolumeLabel;
   ULONG SectorCount;
   ULONG RootDirSectors;
   ULONG TmpVal1;
@@ -290,10 +290,7 @@ Fat12Format (HANDLE  FileHandle,
   SectorCount = PartitionInfo->PartitionLength.QuadPart >>
     GetShiftCount(DiskGeometry->BytesPerSector); /* Use shifting to avoid 64-bit division */
 
-//  SectorCount =
-//    PartitionInfo->PartitionLength.u.LowPart / DiskGeometry->BytesPerSector;
-
-  DPRINT1("SectorCount = %lu\n", SectorCount);
+  DPRINT("SectorCount = %lu\n", SectorCount);
 
   memset(&BootSector, 0, sizeof(FAT16_BOOT_SECTOR));
   memcpy(&BootSector.OEMName[0], "MSWIN4.1", 8);
@@ -307,7 +304,7 @@ Fat12Format (HANDLE  FileHandle,
   BootSector.FATSectors = 0;  /* Set later. See below. */
   BootSector.SectorsPerTrack = DiskGeometry->SectorsPerTrack;
   BootSector.Heads = DiskGeometry->TracksPerCylinder;
-  BootSector.HiddenSectors = DiskGeometry->SectorsPerTrack; //PartitionInfo->HiddenSectors; /* FIXME: Hack! */
+  BootSector.HiddenSectors = PartitionInfo->HiddenSectors;
   BootSector.SectorsHuge = (SectorCount >= 0x10000) ? (unsigned long)SectorCount : 0;
   BootSector.Drive = 0xff; /* No BIOS boot drive available */
   BootSector.ExtBootSignature = 0x29;
@@ -318,24 +315,25 @@ Fat12Format (HANDLE  FileHandle,
     }
   else
     {
-      RtlUnicodeStringToAnsiString(&VolumeLabel, Label, TRUE);
+      RtlUnicodeStringToOemString(&VolumeLabel, Label, TRUE);
       memset(&BootSector.VolumeLabel[0], ' ', 11);
       memcpy(&BootSector.VolumeLabel[0], VolumeLabel.Buffer,
         VolumeLabel.Length < 11 ? VolumeLabel.Length : 11);
-      RtlFreeAnsiString(&VolumeLabel);
+      RtlFreeOemString(&VolumeLabel);
     }
   memcpy(&BootSector.SysType[0], "FAT12   ", 8);
 
   RootDirSectors = ((BootSector.RootEntries * 32) +
     (BootSector.BytesPerSector - 1)) / BootSector.BytesPerSector;
 
-  /* 341 FAT entries (12bit) fit into one 512 byte sector */
+  /* Calculate number of FAT sectors */
+  /* ((BootSector.BytesPerSector * 2) / 3) FAT entries (12bit) fit into one sector */
   TmpVal1 = SectorCount - (BootSector.ReservedSectors + RootDirSectors);
-  TmpVal2 = (341 * BootSector.SectorsPerCluster) + BootSector.FATCount;
+  TmpVal2 = (((BootSector.BytesPerSector * 2) / 3) * BootSector.SectorsPerCluster) + BootSector.FATCount;
   TmpVal3 = (TmpVal1 + (TmpVal2 - 1)) / TmpVal2;
   BootSector.FATSectors = (unsigned short)(TmpVal3 & 0xffff);
 
-  DPRINT1("BootSector.FATSectors = %hx\n", BootSector.FATSectors);
+  DPRINT("BootSector.FATSectors = %hx\n", BootSector.FATSectors);
 
   Status = Fat12WriteBootSector(FileHandle,
     &BootSector);
diff --git a/reactos/lib/fslib/vfatlib/fat16.c b/reactos/lib/fslib/vfatlib/fat16.c
index 3beb4dfe4ef..60785c6d8ce 100644
--- a/reactos/lib/fslib/vfatlib/fat16.c
+++ b/reactos/lib/fslib/vfatlib/fat16.c
@@ -275,7 +275,7 @@ Fat16Format (HANDLE  FileHandle,
 	     PFMIFSCALLBACK  Callback)
 {
   FAT16_BOOT_SECTOR BootSector;
-  ANSI_STRING VolumeLabel;
+  OEM_STRING VolumeLabel;
   ULONG SectorCount;
   ULONG RootDirSectors;
   ULONG TmpVal1;
@@ -323,7 +323,7 @@ Fat16Format (HANDLE  FileHandle,
   BootSector.FATSectors = 0;  /* Set later. See below. */
   BootSector.SectorsPerTrack = DiskGeometry->SectorsPerTrack;
   BootSector.Heads = DiskGeometry->TracksPerCylinder;
-  BootSector.HiddenSectors = DiskGeometry->SectorsPerTrack; //PartitionInfo->HiddenSectors; /* FIXME: Hack! */
+  BootSector.HiddenSectors = PartitionInfo->HiddenSectors;
   BootSector.SectorsHuge = (SectorCount >= 0x10000) ? (unsigned long)SectorCount : 0;
   BootSector.Drive = 0xff; /* No BIOS boot drive available */
   BootSector.ExtBootSignature = 0x29;
@@ -334,11 +334,11 @@ Fat16Format (HANDLE  FileHandle,
     }
   else
     {
-      RtlUnicodeStringToAnsiString(&VolumeLabel, Label, TRUE);
+      RtlUnicodeStringToOemString(&VolumeLabel, Label, TRUE);
       memset(&BootSector.VolumeLabel[0], ' ', 11);
       memcpy(&BootSector.VolumeLabel[0], VolumeLabel.Buffer,
         VolumeLabel.Length < 11 ? VolumeLabel.Length : 11);
-      RtlFreeAnsiString(&VolumeLabel);
+      RtlFreeOemString(&VolumeLabel);
     }
   memcpy(&BootSector.SysType[0], "FAT16   ", 8);
 
@@ -347,13 +347,13 @@ Fat16Format (HANDLE  FileHandle,
   RootDirSectors = ((BootSector.RootEntries * 32) +
     (BootSector.BytesPerSector - 1)) / BootSector.BytesPerSector;
 
-  /* 265 FAT entries (16bit) fit into one 512 byte sector */
+  /* Calculate number of FAT sectors */
+  /* (BootSector.BytesPerSector / 2) FAT entries (16bit) fit into one sector */
   TmpVal1 = SectorCount - (BootSector.ReservedSectors + RootDirSectors);
-  TmpVal2 = (256 * BootSector.SectorsPerCluster) + BootSector.FATCount;
+  TmpVal2 = ((BootSector.BytesPerSector / 2) * BootSector.SectorsPerCluster) + BootSector.FATCount;
   TmpVal3 = (TmpVal1 + (TmpVal2 - 1)) / TmpVal2;
   BootSector.FATSectors = (unsigned short)(TmpVal3 & 0xffff);
-
-  DPRINT("BootSector.FATSectors = %hx\n", BootSector.FATSectors);
+  DPRINT("BootSector.FATSectors = %hu\n", BootSector.FATSectors);
 
   Status = Fat16WriteBootSector(FileHandle,
     &BootSector);
diff --git a/reactos/lib/fslib/vfatlib/fat32.c b/reactos/lib/fslib/vfatlib/fat32.c
index 4db82d7dbaf..9f651de2649 100644
--- a/reactos/lib/fslib/vfatlib/fat32.c
+++ b/reactos/lib/fslib/vfatlib/fat32.c
@@ -344,11 +344,10 @@ Fat32Format (HANDLE  FileHandle,
 	     PFMIFSCALLBACK  Callback)
 {
   FAT32_BOOT_SECTOR BootSector;
-  ANSI_STRING VolumeLabel;
+  OEM_STRING VolumeLabel;
   ULONG RootDirSectors;
   ULONG TmpVal1;
   ULONG TmpVal2;
-  ULONG TmpVal3;
   NTSTATUS Status;
 
   /* Calculate cluster size */
@@ -388,7 +387,7 @@ Fat32Format (HANDLE  FileHandle,
   BootSector.FATSectors = 0;
   BootSector.SectorsPerTrack = DiskGeometry->SectorsPerTrack;
   BootSector.Heads = DiskGeometry->TracksPerCylinder;
-  BootSector.HiddenSectors = DiskGeometry->SectorsPerTrack; //PartitionInfo->HiddenSectors; /* FIXME: Hack! */
+  BootSector.HiddenSectors = PartitionInfo->HiddenSectors;
   BootSector.SectorsHuge = PartitionInfo->PartitionLength.QuadPart >>
     GetShiftCount(BootSector.BytesPerSector); /* Use shifting to avoid 64-bit division */
   BootSector.FATSectors32 = 0; /* Set later */
@@ -406,45 +405,23 @@ Fat32Format (HANDLE  FileHandle,
     }
   else
     {
-      RtlUnicodeStringToAnsiString(&VolumeLabel, Label, TRUE);
+      RtlUnicodeStringToOemString(&VolumeLabel, Label, TRUE);
       memset(&BootSector.VolumeLabel[0], ' ', 11);
       memcpy(&BootSector.VolumeLabel[0], VolumeLabel.Buffer,
         VolumeLabel.Length < 11 ? VolumeLabel.Length : 11);
-      RtlFreeAnsiString(&VolumeLabel);
+      RtlFreeOemString(&VolumeLabel);
     }
   memcpy(&BootSector.SysType[0], "FAT32   ", 8);
 
   RootDirSectors = ((BootSector.RootEntries * 32) +
     (BootSector.BytesPerSector - 1)) / BootSector.BytesPerSector;
-  TmpVal1 = BootSector.SectorsHuge - (BootSector.ReservedSectors + RootDirSectors);
-  TmpVal2 = (256 * BootSector.SectorsPerCluster) + BootSector.FATCount;
-  if (TRUE /* FAT32 */)
-    {
-      TmpVal2 = 0;
-      do
-        {
-          if (TmpVal2 == 0)
-	    {
-	      TmpVal3 = 0xffffffff;
-	    }
-	  else
-	    {
-	      TmpVal3 = TmpVal2;
-	    }
-          TmpVal2 = ((TmpVal1 - TmpVal2 * BootSector.FATCount) / BootSector.SectorsPerCluster) + 2;
-	  TmpVal2 = (sizeof(ULONG) * TmpVal2 + BootSector.BytesPerSector - 1) / BootSector.BytesPerSector;
-        }
-      while (TmpVal3 > TmpVal2);
-      BootSector.FATSectors32 = TmpVal2;
-    }
 
-#if 0
-  /* experimental */
-  /* 128 FAT entries (32bit) fit into one 512 byte sector */
+  /* Calculate number of FAT sectors */
+  /* (BytesPerSector / 4) FAT entries (32bit) fit into one sector */
   TmpVal1 = BootSector.SectorsHuge - BootSector.ReservedSectors;
-  TmpVal2 = (128 * BootSector.SectorsPerCluster) + BootSector.FATCount;
+  TmpVal2 = ((BootSector.BytesPerSector / 4) * BootSector.SectorsPerCluster) + BootSector.FATCount;
   BootSector.FATSectors32 = (TmpVal1 + (TmpVal2 - 1)) / TmpVal2;
-#endif
+  DPRINT("FATSectors32 = %lu\n", BootSector.FATSectors32);
 
   Status = Fat32WriteBootSector(FileHandle,
     &BootSector);
diff --git a/reactos/lib/fslib/vfatlib/vfatlib.c b/reactos/lib/fslib/vfatlib/vfatlib.c
index 8667f317ea2..2851f1a31b7 100755
--- a/reactos/lib/fslib/vfatlib/vfatlib.c
+++ b/reactos/lib/fslib/vfatlib/vfatlib.c
@@ -107,6 +107,12 @@ VfatFormat(
           NtClose(FileHandle);
           return Status;
         }
+
+      /*
+       * FIXME: This is a hack!
+       *        Partitioning software MUST set the correct number of hidden sectors!
+       */
+      PartitionInfo.HiddenSectors = DiskGeometry.SectorsPerTrack;
     }
   else
     {
@@ -118,10 +124,10 @@ VfatFormat(
 	(ULONGLONG)DiskGeometry.SectorsPerTrack *
 	(ULONGLONG)DiskGeometry.BytesPerSector;
       PartitionInfo.HiddenSectors = 0;
-      PartitionInfo.PartitionNumber = 1;
+      PartitionInfo.PartitionNumber = 0;
       PartitionInfo.BootIndicator = FALSE;
       PartitionInfo.RewritePartition = FALSE;
-      PartitionInfo.RecognizedPartition = TRUE;
+      PartitionInfo.RecognizedPartition = FALSE;
     }
 
   DPRINT("PartitionType 0x%x\n", PartitionInfo.PartitionType);