diff --git a/dlls/ole32/usrmarshal.c b/dlls/ole32/usrmarshal.c
index 7555793e3a5..fe5e474f6d2 100644
--- a/dlls/ole32/usrmarshal.c
+++ b/dlls/ole32/usrmarshal.c
@@ -79,9 +79,9 @@ static void dump_user_flags(unsigned long *pFlags)
  *  the first parameter is an unsigned long.
  *  This function is only intended to be called by the RPC runtime.
  */
-unsigned long __RPC_USER CLIPFORMAT_UserSize(unsigned long *pFlags, unsigned long StartingSize, CLIPFORMAT *pCF)
+ULONG __RPC_USER CLIPFORMAT_UserSize(ULONG *pFlags, ULONG StartingSize, CLIPFORMAT *pCF)
 {
-    unsigned long size = StartingSize;
+    ULONG size = StartingSize;
 
     TRACE("("); dump_user_flags(pFlags); TRACE(", %ld, %p\n", StartingSize, pCF);
 
@@ -240,7 +240,7 @@ void __RPC_USER CLIPFORMAT_UserFree(unsigned long *pFlags, CLIPFORMAT *pCF)
      * so nothing to do */
 }
 
-static unsigned long __RPC_USER handle_UserSize(unsigned long *pFlags, unsigned long StartingSize, HANDLE *handle)
+static ULONG __RPC_USER handle_UserSize(ULONG *pFlags, ULONG StartingSize, HANDLE *handle)
 {
     if (LOWORD(*pFlags) == MSHCTX_DIFFERENTMACHINE)
     {
@@ -280,7 +280,7 @@ static void __RPC_USER handle_UserFree(unsigned long *pFlags, HANDLE *phMenu)
 }
 
 #define IMPL_WIREM_HANDLE(type) \
-    unsigned long __RPC_USER type##_UserSize(unsigned long *pFlags, unsigned long StartingSize, type *handle) \
+    ULONG __RPC_USER type##_UserSize(ULONG *pFlags, ULONG StartingSize, type *handle) \
     { \
         TRACE("("); dump_user_flags(pFlags); TRACE(", %ld, %p\n", StartingSize, handle); \
         return handle_UserSize(pFlags, StartingSize, (HANDLE *)handle); \
@@ -311,9 +311,9 @@ IMPL_WIREM_HANDLE(HWND)
 /******************************************************************************
  *           HGLOBAL_UserSize [OLE32.@]
  */
-unsigned long __RPC_USER HGLOBAL_UserSize(unsigned long *pFlags, unsigned long StartingSize, HGLOBAL *phGlobal)
+ULONG __RPC_USER HGLOBAL_UserSize(ULONG *pFlags, ULONG StartingSize, HGLOBAL *phGlobal)
 {
-    unsigned long size = StartingSize;
+    ULONG size = StartingSize;
 
     TRACE("("); dump_user_flags(pFlags); TRACE(", %ld, %p\n", StartingSize, phGlobal);
 
@@ -331,7 +331,7 @@ unsigned long __RPC_USER HGLOBAL_UserSize(unsigned long *pFlags, unsigned long S
             SIZE_T ret;
             size += 3 * sizeof(ULONG);
             ret = GlobalSize(*phGlobal);
-            size += (unsigned long)ret;
+            size += (ULONG)ret;
         }
     }
     
@@ -457,7 +457,7 @@ void __RPC_USER HGLOBAL_UserFree(unsigned long *pFlags, HGLOBAL *phGlobal)
         GlobalFree(*phGlobal);
 }
 
-unsigned long __RPC_USER HBITMAP_UserSize(unsigned long *pFlags, unsigned long StartingSize, HBITMAP *phBmp)
+ULONG __RPC_USER HBITMAP_UserSize(ULONG *pFlags, ULONG StartingSize, HBITMAP *phBmp)
 {
     FIXME(":stub\n");
     return StartingSize;
@@ -480,7 +480,7 @@ void __RPC_USER HBITMAP_UserFree(unsigned long *pFlags, HBITMAP *phBmp)
     FIXME(":stub\n");
 }
 
-unsigned long __RPC_USER HDC_UserSize(unsigned long *pFlags, unsigned long StartingSize, HDC *phdc)
+ULONG __RPC_USER HDC_UserSize(ULONG *pFlags, ULONG StartingSize, HDC *phdc)
 {
     FIXME(":stub\n");
     return StartingSize;
@@ -503,7 +503,7 @@ void __RPC_USER HDC_UserFree(unsigned long *pFlags, HDC *phdc)
     FIXME(":stub\n");
 }
 
-unsigned long __RPC_USER HPALETTE_UserSize(unsigned long *pFlags, unsigned long StartingSize, HPALETTE *phPal)
+ULONG __RPC_USER HPALETTE_UserSize(ULONG *pFlags, ULONG StartingSize, HPALETTE *phPal)
 {
     FIXME(":stub\n");
     return StartingSize;
@@ -527,9 +527,9 @@ void __RPC_USER HPALETTE_UserFree(unsigned long *pFlags, HPALETTE *phPal)
 }
 
 
-unsigned long __RPC_USER HENHMETAFILE_UserSize(unsigned long *pFlags, unsigned long StartingSize, HENHMETAFILE *phEmf)
+ULONG __RPC_USER HENHMETAFILE_UserSize(ULONG *pFlags, ULONG StartingSize, HENHMETAFILE *phEmf)
 {
-    unsigned long size = StartingSize;
+    ULONG size = StartingSize;
 
     TRACE("("); dump_user_flags(pFlags); TRACE(", %ld, %p\n", StartingSize, *phEmf);
 
@@ -643,9 +643,9 @@ void __RPC_USER HENHMETAFILE_UserFree(unsigned long *pFlags, HENHMETAFILE *phEmf
         DeleteEnhMetaFile(*phEmf);
 }
 
-unsigned long __RPC_USER STGMEDIUM_UserSize(unsigned long *pFlags, unsigned long StartingSize, STGMEDIUM *pStgMedium)
+ULONG __RPC_USER STGMEDIUM_UserSize(ULONG *pFlags, ULONG StartingSize, STGMEDIUM *pStgMedium)
 {
-    unsigned long size = StartingSize;
+    ULONG size = StartingSize;
 
     TRACE("("); dump_user_flags(pFlags); TRACE(", %ld, %p\n", StartingSize, pStgMedium);
 
@@ -812,7 +812,7 @@ void __RPC_USER STGMEDIUM_UserFree(unsigned long *pFlags, STGMEDIUM *pStgMedium)
     ReleaseStgMedium(pStgMedium);
 }
 
-unsigned long __RPC_USER ASYNC_STGMEDIUM_UserSize(unsigned long *pFlags, unsigned long StartingSize, ASYNC_STGMEDIUM *pStgMedium)
+ULONG __RPC_USER ASYNC_STGMEDIUM_UserSize(ULONG *pFlags, ULONG StartingSize, ASYNC_STGMEDIUM *pStgMedium)
 {
     FIXME(":stub\n");
     return StartingSize;
@@ -835,7 +835,7 @@ void __RPC_USER ASYNC_STGMEDIUM_UserFree(unsigned long *pFlags, ASYNC_STGMEDIUM
     FIXME(":stub\n");
 }
 
-unsigned long __RPC_USER FLAG_STGMEDIUM_UserSize(unsigned long *pFlags, unsigned long StartingSize, FLAG_STGMEDIUM *pStgMedium)
+ULONG __RPC_USER FLAG_STGMEDIUM_UserSize(ULONG *pFlags, ULONG StartingSize, FLAG_STGMEDIUM *pStgMedium)
 {
     FIXME(":stub\n");
     return StartingSize;
@@ -858,7 +858,7 @@ void __RPC_USER FLAG_STGMEDIUM_UserFree(unsigned long *pFlags, FLAG_STGMEDIUM *p
     FIXME(":stub\n");
 }
 
-unsigned long __RPC_USER SNB_UserSize(unsigned long *pFlags, unsigned long StartingSize, SNB *pSnb)
+ULONG __RPC_USER SNB_UserSize(ULONG *pFlags, ULONG StartingSize, SNB *pSnb)
 {
     FIXME(":stub\n");
     return StartingSize;
diff --git a/dlls/oleaut32/usrmarshal.c b/dlls/oleaut32/usrmarshal.c
index ddc55a268de..17e2479d41c 100644
--- a/dlls/oleaut32/usrmarshal.c
+++ b/dlls/oleaut32/usrmarshal.c
@@ -85,7 +85,7 @@ static void dump_user_flags(unsigned long *pFlags)
 #define CLS_TYPEATTR  't'
 #define CLS_VARDESC   'v'
 
-unsigned long WINAPI CLEANLOCALSTORAGE_UserSize(unsigned long *pFlags, unsigned long Start, CLEANLOCALSTORAGE *pstg)
+ULONG WINAPI CLEANLOCALSTORAGE_UserSize(ULONG *pFlags, ULONG Start, CLEANLOCALSTORAGE *pstg)
 {
     ALIGN_LENGTH(Start, 3);
     return Start + sizeof(DWORD);
@@ -142,7 +142,7 @@ typedef struct
     DWORD len2;         /* == len */
 } bstr_wire_t;
 
-unsigned long WINAPI BSTR_UserSize(unsigned long *pFlags, unsigned long Start, BSTR *pstr)
+ULONG WINAPI BSTR_UserSize(ULONG *pFlags, ULONG Start, BSTR *pstr)
 {
     TRACE("(%lx,%ld,%p) => %p\n", *pFlags, Start, pstr, *pstr);
     if (*pstr) TRACE("string=%s\n", debugstr_w(*pstr));
@@ -424,7 +424,7 @@ static unsigned char *interface_variant_unmarshal(unsigned long *pFlags, unsigne
 }
 
 
-unsigned long WINAPI VARIANT_UserSize(unsigned long *pFlags, unsigned long Start, VARIANT *pvar)
+ULONG WINAPI VARIANT_UserSize(ULONG *pFlags, ULONG Start, VARIANT *pvar)
 {
     int align;
     TRACE("(%lx,%ld,%p)\n", *pFlags, Start, pvar);
@@ -732,9 +732,9 @@ static inline SF_TYPE SAFEARRAY_GetUnionType(SAFEARRAY *psa)
     }
 }
 
-unsigned long WINAPI LPSAFEARRAY_UserSize(unsigned long *pFlags, unsigned long StartingSize, LPSAFEARRAY *ppsa)
+ULONG WINAPI LPSAFEARRAY_UserSize(ULONG *pFlags, ULONG StartingSize, LPSAFEARRAY *ppsa)
 {
-    unsigned long size = StartingSize;
+    ULONG size = StartingSize;
 
     TRACE("("); dump_user_flags(pFlags); TRACE(", %ld, %p\n", StartingSize, *ppsa);
 
diff --git a/tools/widl/header.c b/tools/widl/header.c
index 9d816ef09ae..b149fb452e8 100644
--- a/tools/widl/header.c
+++ b/tools/widl/header.c
@@ -332,7 +332,7 @@ void write_user_types(void)
   for (ut = user_type_list; ut; ut = ut->next)
   {
     const char *name = ut->name;
-    fprintf(header, "unsigned long   __RPC_USER %s_UserSize     (unsigned long *, unsigned long,   %s *);\n", name, name);
+    fprintf(header, "ULONG           __RPC_USER %s_UserSize     (ULONG *, ULONG, %s *);\n", name, name);
     fprintf(header, "unsigned char * __RPC_USER %s_UserMarshal  (unsigned long *, unsigned char *, %s *);\n", name, name);
     fprintf(header, "unsigned char * __RPC_USER %s_UserUnmarshal(unsigned long *, unsigned char *, %s *);\n", name, name);
     fprintf(header, "void            __RPC_USER %s_UserFree     (unsigned long *, %s *);\n", name, name);