Index: clipboard.c
===================================================================
--- win32ss/user/ntuser/clipboard.c	(revision 75017)
+++ win32ss/user/ntuser/clipboard.c	(working copy)
@@ -448,9 +448,14 @@
     {
         /* Return next format */
         pElement = IntGetFormatElement(pWinStaObj, fmt);
-        ++pElement;
-        if (pElement < &pWinStaObj->pClipBase[pWinStaObj->cNumClipFormats])
-            Ret = pElement->fmt;
+        if (pElement != NULL)
+        {
+            ++pElement;
+            if (pElement < &pWinStaObj->pClipBase[pWinStaObj->cNumClipFormats])
+            {
+                Ret = pElement->fmt;
+            }
+        }
     }
 
 cleanup:
Index: main.c
===================================================================
--- win32ss/user/ntuser/main.c	(revision 75017)
+++ win32ss/user/ntuser/main.c	(working copy)
@@ -708,6 +708,8 @@
     ptiCurrent->TIF_flags |= TIF_DONTATTACHQUEUE;
     ptiCurrent->pClientInfo->dwTIFlags = ptiCurrent->TIF_flags;
 
+    UserCloseClipboard();
+
     /* Decrement thread count and check if its 0 */
     ppiCurrent->cThreads--;