Try the usual cure: find and delete normal.dot. If it is somehow corrupted, things like this can happen.
If that doesn't help, post more details on the error message and the conditions that lead to it.
Kees
Ever since I installed Office XP Professional Word crashes/saves or recovers/behaves for a day. Now it crashes constantly. HELP!

Chowhound
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GameFAQs
GameSpot
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TechRepublic