diff --git a/reactos/include/psdk/winuser.h b/reactos/include/psdk/winuser.h
index 8daa3f1a914..bb87c61f3d5 100644
--- a/reactos/include/psdk/winuser.h
+++ b/reactos/include/psdk/winuser.h
@@ -2797,7 +2797,7 @@ typedef struct tagCWPRETSTRUCT {
 	WPARAM wParam;
 	DWORD message;
 	HWND hwnd;
-} CWPRETSTRUCT;
+} CWPRETSTRUCT,*PCWPRETSTRUCT, *LPCWPRETSTRUCT;
 typedef struct tagCWPSTRUCT {
 	LPARAM lParam;
 	WPARAM wParam;
@@ -3190,6 +3190,20 @@ typedef struct tagMOUSEHOOKSTRUCT {
 	UINT wHitTestCode;
 	DWORD dwExtraInfo;
 } MOUSEHOOKSTRUCT,*LPMOUSEHOOKSTRUCT,*PMOUSEHOOKSTRUCT;
+#if ( _WIN32_WINNT >= 0x0500 )
+#ifdef __cplusplus
+typedef struct tagMOUSEHOOKSTRUCTEX : public tagMOUSEHOOKSTRUCT
+{
+        DWORD   mouseData;
+} MOUSEHOOKSTRUCTEX, *LPMOUSEHOOKSTRUCTEX, *PMOUSEHOOKSTRUCTEX;
+#else
+typedef struct tagMOUSEHOOKSTRUCTEX
+{
+        MOUSEHOOKSTRUCT MOUSEHOOKSTRUCT;
+        DWORD   mouseData;
+} MOUSEHOOKSTRUCTEX, *LPMOUSEHOOKSTRUCTEX, *PMOUSEHOOKSTRUCTEX;
+#endif
+#endif
 typedef struct tagTRACKMOUSEEVENT {
 	DWORD cbSize;
 	DWORD dwFlags;