diff --git a/win32ss/user/ntuser/clipboard.c b/win32ss/user/ntuser/clipboard.c
index d144220a18..9da9148e25 100644
--- a/win32ss/user/ntuser/clipboard.c
+++ b/win32ss/user/ntuser/clipboard.c
@@ -377,7 +377,16 @@ UserClipboardRelease(PWND pWindow)
 
     pWinStaObj = IntGetWinStaForCbAccess();
     if (!pWinStaObj)
+    {
+        ERR("pWinStaObj was NULL.\n");  
         return;
+    }
+
+    if (!pWindow)
+    {
+        ERR("pWindow was NULL.\n");     
+        return;
+    }
 
     co_IntSendMessage(pWinStaObj->spwndClipOwner->head.h, WM_RENDERALLFORMATS, 0, 0);