diff --git a/reactos/subsys/win32k/eng/surface.c b/reactos/subsys/win32k/eng/surface.c
index 9d26608510a..820ea1f4673 100644
--- a/reactos/subsys/win32k/eng/surface.c
+++ b/reactos/subsys/win32k/eng/surface.c
@@ -16,7 +16,7 @@
  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
-/* $Id: surface.c,v 1.34 2004/03/17 16:05:29 navaraf Exp $
+/* $Id: surface.c,v 1.35 2004/03/20 17:33:10 navaraf Exp $
  * 
  * COPYRIGHT:         See COPYING in the top level directory
  * PROJECT:           ReactOS kernel
@@ -506,6 +506,8 @@ EngModifySurface(
 
    if (!EngAssociateSurface(hsurf, hdev, flHooks))
    {
+      EngUnlockSurface(pso);
+
       return FALSE;
    }