Unhandled Exception Error

message from =?Utf-8?B?UFJMNTE4?= on 4 Jun 2004
When I open a user I get a an error: Unhandled Exception: C0000005
At Address: 100016b8

What do I need to do to fix this?
 

Archived message: Unhandled Exception Error (Microsoft WinXP)
 
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