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Thunderbird frequently locks up, Not Responing in Win 8.1

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  • 6 have this problem
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  • Last reply by Matt

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Thunderbird will lock up and the screen goes blank and says 'Thunderbird is not responding'. I try to close it and it takes much time to close. I try to use task manager and I can see it is using nearly half of the cpu capacity and a large amount of memory. I cannot end task using task manager. I am running windows 8.1. This happens on more than one computer.

Thunderbird will lock up and the screen goes blank and says 'Thunderbird is not responding'. I try to close it and it takes much time to close. I try to use task manager and I can see it is using nearly half of the cpu capacity and a large amount of memory. I cannot end task using task manager. I am running windows 8.1. This happens on more than one computer.

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See https://wiki.mozilla.org/Thunderbird:Testing:Antivirus_Related_Performance_Issues

To diagnose problems with Thunderbird, try one of the following:

  • Restart Thunderbird with add-ons disabled (Thunderbird Safe Mode). On the Help menu, click on "Restart with Add-ons Disabled". If Thunderbird works like normal, there is an Add-on or Theme interfering with normal operations. You will need to re-enable add-ons one at a time until you locate the offender.
  • Restart the operating system in safe mode with Networking. This loads only the very basics needed to start your computer while enabling an Internet connection. Click on your operating system for instructions on how to start in safe mode: Windows 8, Windows 7, Windows Vista, Windows XP, OSX
If safe mode for the operating system fixes the issue, there's other software in your computer that's causing problems. Possibilities include but not limited to: AV scanning, virus/malware, background downloads such as program updates.