diff --git a/dll/win32/advapi32/wine/crypt.c b/dll/win32/advapi32/wine/crypt.c
index a7e130c86c9..27e70585731 100644
--- a/dll/win32/advapi32/wine/crypt.c
+++ b/dll/win32/advapi32/wine/crypt.c
@@ -604,7 +604,7 @@ BOOL WINAPI CryptAcquireContextA (HCRYPTPROV *phProv, LPCSTR pszContainer,
  * PARAMS
  *  hProv       [I] Handle to the CSP whose reference is being incremented.
  *  pdwReserved [IN] Reserved for future use and must be NULL.
- *  dwFlags     [I] Reserved for future use and must be NULL.
+ *  dwFlags     [I] Reserved for future use and must be 0.
  *
  * RETURNS
  *  Success: TRUE
@@ -628,7 +628,7 @@ BOOL WINAPI CryptContextAddRef (HCRYPTPROV hProv, DWORD *pdwReserved, DWORD dwFl
 		return FALSE;
 	}
 
-	pProv->refcount++;
+	InterlockedIncrement(&pProv->refcount);
 	return TRUE;
 }
 
@@ -654,7 +654,7 @@ BOOL WINAPI CryptReleaseContext (HCRYPTPROV hProv, DWORD dwFlags)
 
 	if (!pProv)
 	{
-		SetLastError(NTE_BAD_UID);
+		SetLastError(ERROR_INVALID_PARAMETER);
 		return FALSE;
 	}
 
@@ -664,8 +664,7 @@ BOOL WINAPI CryptReleaseContext (HCRYPTPROV hProv, DWORD dwFlags)
 		return FALSE;
 	}
 
-	pProv->refcount--;
-	if (pProv->refcount <= 0) 
+	if (InterlockedDecrement(&pProv->refcount) == 0)
 	{
 		ret = pProv->pFuncs->pCPReleaseContext(pProv->hPrivate, dwFlags);
 		pProv->dwMagic = 0;
@@ -728,7 +727,7 @@ BOOL WINAPI CryptGenRandom (HCRYPTPROV hProv, DWORD dwLen, BYTE *pbBuffer)
  *  hProv   [I] Handle of a CSP.
  *  Algid   [I] Identifies the hash algorithm to use.
  *  hKey    [I] Key for the hash (if required).
- *  dwFlags [I] Reserved for future use and must be NULL.
+ *  dwFlags [I] Reserved for future use and must be 0.
  *  phHash  [O] Address of the future handle to the new hash object.
  *
  * RETURNS
@@ -963,7 +962,7 @@ BOOL WINAPI CryptDestroyKey (HCRYPTKEY hKey)
  *
  * PARAMS
  *  hHash       [I] Handle to the hash to be copied.
- *  pdwReserved [I] Reserved for future use and must be zero.
+ *  pdwReserved [I] Reserved for future use and must be NULL.
  *  dwFlags     [I] Reserved for future use and must be zero.
  *  phHash      [O] Address of the handle to receive the copy.
  *
diff --git a/dll/win32/advapi32/wine/crypt.h b/dll/win32/advapi32/wine/crypt.h
index 75cf937fda2..0b101bb0b01 100644
--- a/dll/win32/advapi32/wine/crypt.h
+++ b/dll/win32/advapi32/wine/crypt.h
@@ -21,11 +21,13 @@
 #ifndef __WINE_CRYPT_H
 #define __WINE_CRYPT_H
 
-//#include <stdarg.h>
+#ifndef __REACTOS__
+#include <stdarg.h>
 
-//#include "windef.h"
-//#include "winbase.h"
-//#include "wincrypt.h"
+#include "windef.h"
+#include "winbase.h"
+#include "wincrypt.h"
+#endif
 
 typedef struct tagPROVFUNCS
 {
@@ -63,7 +65,7 @@ typedef struct tagPROVFUNCS
 typedef struct tagCRYPTPROV
 {
 	DWORD dwMagic;
-	UINT refcount;
+	LONG refcount;
 	HMODULE hModule;
 	PPROVFUNCS pFuncs;
         HCRYPTPROV hPrivate;  /*CSP's handle - Should not be given to application under any circumstances!*/