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What does nsAppShell: Event Window mean? Firefox won't open for me at times and I need to restart.

  • 5 replies
  • 1187 have this problem
  • 8 views
  • Last reply by BleuVII

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When I return to my computer, Firefox won't open from the "standby" mode. It gives me the message saying "Firefox is already running, but not responding" and I need to log out or restart. Firefox is not running as far as I know. When I restart, a message comes up asking if I want to close "nsAppShell: Event Window". Once I end this process, it restarts my computer and everything is fine. This is very frustrating and happens all the time. What is "nsAppShell: Event Window"?

When I return to my computer, Firefox won't open from the "standby" mode. It gives me the message saying "Firefox is already running, but not responding" and I need to log out or restart. Firefox is not running as far as I know. When I restart, a message comes up asking if I want to close "nsAppShell: Event Window". Once I end this process, it restarts my computer and everything is fine. This is very frustrating and happens all the time. What is "nsAppShell: Event Window"?

All Replies (5)

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What does nsAppShell: Event Window mean? Firefox won't open for me at times and I need to restart.

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Restart or even shut down doesn't solve the problem for me. I just cannot start Firefox. What should I do?

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The OP asked this question 9 months ago and 850 other people have this problem. Why hasn't Firefox Support answered this question or commented?

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untill now no body from supporting team can reply us to solve this problem , better uninstall Firfox browser and use another program

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I searched elsewhere, and found that nsAppShell is part of firefox itself, which is why other internet programs work fine.

One of common threads for everyone asking this question was AdBlock Plus. I just removed the add-on, and we'll see if that fixes the problem.

For record's sake, I also had the x3watch accountability program installed, and it often timed out at the same time as nsAppShell: Event Window. I have re-installed it. Now I just have to wait and see.