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What is NSAppshell event window and how can I remove it? Have tried disabling all plug-ins and add-ons and it's still there and makes our computer slower than dial up!


Whenever I log off of my computer I get a message "NSAppshell event window," which slows down the performance of Mozilla and anything else we're trying to run on our computer. We're forced to log off and on to reboot and this happens nearly all the time. We have tried disabling all add-ons and plug-ins, to no avail. We are using Mozilla 4.0. Thanks for any help you can provide, as we don't want to go back to using Internet Explorer if we can help it.

Additional System Details

This happened

Every time Firefox opened

This started when...

Shortly after installing Mozilla 3.6 and now again with Mozilla 4.0. It's been happening for several months now.


  • User Agent: Mozilla/5.0 (Windows NT 5.1; rv:2.0) Gecko/20100101 Firefox/4.0

More Information

Blake Moore 1 solutions 7 answers

I'd like you to upgrade to the latest version of Firefox, and tell me if that fixes your problem.