diff --git a/reactos/subsystems/win32/win32k/ntuser/message.c b/reactos/subsystems/win32/win32k/ntuser/message.c
index 7bee1f37f32..0dcf17b8b02 100644
--- a/reactos/subsystems/win32/win32k/ntuser/message.c
+++ b/reactos/subsystems/win32/win32k/ntuser/message.c
@@ -1550,6 +1550,8 @@ co_IntDoSendMessage(HWND hWnd,
          MmCopyToCaller(UnsafeInfo, &Info, sizeof(NTUSERSENDMESSAGEINFO));
          return 0;
       }
+      if (!Window->Wnd)
+         return 0;
    }
 
    /* FIXME: Check for an exiting window. */
diff --git a/reactos/subsystems/win32/win32k/ntuser/monitor.c b/reactos/subsystems/win32/win32k/ntuser/monitor.c
index a3e2121ffb5..d93047b966d 100644
--- a/reactos/subsystems/win32/win32k/ntuser/monitor.c
+++ b/reactos/subsystems/win32/win32k/ntuser/monitor.c
@@ -899,6 +899,9 @@ NtUserMonitorFromWindow(
       RETURN(hMonitor);
    }
 
+   if (!Window->Wnd)
+      RETURN(hMonitor);
+
    Rect.left = Rect.right = Window->Wnd->WindowRect.left;
    Rect.top = Rect.bottom = Window->Wnd->WindowRect.bottom;