| GDI Subsystem Stops Responding (Hangs) and Returns Error Message in VGA ModeID: Q237780 
 | 
When you run a program that uses a Graphics Device Interface (GDI) subsystem on a computer running Windows NT 4.0 in VGA mode, the computer may stop responding (hang) and the following error message may be displayed:
Access to invalid address.
This behavior occurs because the GDI code directs two rectangles to converge in an empty intersection, and the two rectangles appear as a very large, single rectangle to the video adapter driver.
A supported fix that corrects this problem is now available from Microsoft, but 
it has not been fully regression tested and should be applied only to systems 
experiencing this specific problem. If you are not severely affected by this 
specific problem, Microsoft recommends that you wait for the next Windows NT 4.0 service pack 
that contains this fix.
To resolve this problem immediately, contact Microsoft Product Support Services 
to obtain the fix. For a complete list of Microsoft Product Support Services 
phone numbers and information on support costs, please go to the following 
address on the World Wide Web:
http://www.microsoft.com/support/supportnet/overview/overview.aspThe English version of this fix should have the following file attributes or later:
   Date       Time     Size        File name    Platform
   -----------------------------------------------------
   04/28/99   08:37p   1,243,184   Win32k.sys   x86
   04/28/99   08:33p   2,058,608   Win32k.sys   Alpha Q154871 Determining If You Are Eligible for No-Charge Technical Support
Microsoft has confirmed this to be a problem in the Microsoft products listed at the beginning of this article.
Additional query words:
Keywords          : kberrmsg kbgraphic ntsp kbbug4.00 kbfix4.00 NT4SP6Fix 
Version           : winnt:4.0
Platform          : winnt 
Issue type        : kbbug Last Reviewed: July 19, 1999