Ja das passiert nur beim FF.
Hier ist was der Event Viewer dazu sagt:
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Event Type: Information
Event Source: Application Popup
Event Category: None
Event ID: 26
Date: 13.08.2008
Time: 14:22:41
User: N/A
Computer:XXXXXXXX
Description:
Application popup: firefox.exe - Application Error : The instruction at "0x30cb0d78" referenced memory at "0x00000000". The memory could not be "written".
Click on OK to terminate the program
For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
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