Index: reactos/win32ss/gdi/ntgdi/region.c
===================================================================
--- reactos/win32ss/gdi/ntgdi/region.c	(revision 74543)
+++ reactos/win32ss/gdi/ntgdi/region.c	(working copy)
@@ -2088,6 +2088,24 @@
                 NT_ASSERT(FALSE);
             }
 
+            /* Kill all rectangles of width zero and/or height zero */
+            for (i = j = 0; i < prgn->rdh.nCount; ++i)
+            {
+                if (prgn->Buffer[i].left == prgn->Buffer[i].right ||
+                    prgn->Buffer[i].top == prgn->Buffer[i].bottom)
+                {
+                    continue;
+                }
+
+                if (j != i)
+                {
+                    prgn->Buffer[j] = prgn->Buffer[i];
+                }
+                j++;
+            }
+            prgn->rdh.nCount = j;
+            prgn->rdh.nRgnSize = prgn->rdh.nCount * sizeof(RECTL);
+
             /* Reset bounds */
             RECTL_vSetEmptyRect(&prgn->rdh.rcBound);
 
@@ -2103,13 +2121,20 @@
                                  &prgn->Buffer[i]);
             }
 
+            if (prgn->rdh.nCount == 0)
+            {
+                ExFreePoolWithTag(prgn->Buffer, GDITAG_REGION);
+                prgn->Buffer = NULL;
+                return TRUE;
+            }
+
             /* Loop all rects in the region */
             for (i = 0; i < prgn->rdh.nCount - 1; i++)
             {
-                for (j = i; i < prgn->rdh.nCount; i++)
+                for (j = i + 1; j < prgn->rdh.nCount; j++)
                 {
                     NT_ASSERT(prgn->Buffer[i].top < prgn->Buffer[i].bottom);
-                    NT_ASSERT(prgn->Buffer[j].top >= prgn->Buffer[i].top);
+                    NT_ASSERT(prgn->Buffer[i].top <= prgn->Buffer[j].top);
                 }
             }