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Thunderbird locks up. Can't even close it without Task Manager. What to do?

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  • 1 has this problem
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  • Last reply by sfhowes

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I have one message open. Cannot close it, or go back to my Inbox. Cannot close Thunderbird. In other words, no matter where I click, nothing happens. The program will close with Task Manager. I have version 68.4.1 (32-bit).

I have one message open. Cannot close it, or go back to my Inbox. Cannot close Thunderbird. In other words, no matter where I click, nothing happens. The program will close with Task Manager. I have version 68.4.1 (32-bit).

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Close TB, then open the profile folder:

C:\Users\username\AppData\Roaming\Thunderbird\Profiles\8characterstring.default

AppData is hidden by default.

Delete session.json, the file that stores the open tabs at last exit. When you restart TB, right-click the problem message, Delete Message.

The message may have locked the program because it was being scanned by a security app. In general, the profile folder should be excluded from AV scanning.