I usually narrow it down to some application that is crashing on shutdown. If it's very repeatable, the list of programs if you press Control-Alt-Delete can be a good clue to what's running. It's up to you to KNOW each and every one of them since the one you don't know could be a nasty bug or parasite. Tip: Use http://www.google.com and type in the name of the process you don't know.
The Shutdown Article at http://www.aumha.org/articles.htm is always a good read.
Bob
I'm using Windows 98. When I go to Start/ShutDown and try to turn my computer off I get this error message:
"A fatal exception OD has occcurred at 0028:CEAF0201.
The Current Application will be terminated.
*Press any key to terminate the current application
*Press CTRL+ALT+DEL again to restart your computer. You will lose any unsaved information in all applications.
Press any key to continue."
I press a key to continue and get the same message again. I press a key to continue the second time and it starts to close down but doesn't quite finish closing. I have to then hit the on/off button to turn it off. How do I fix that?
Thanks,
John Whitehead

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