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Thunderbird (60.6.1) on Windows 10 (v1809) will not start again after terminating, reporting "Thunderbird is already running, but is not responding."

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  • Last reply by sfhowes

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Recently, after terminating Thunderbird (60.6.1) on Windows 10 (v1809), it will not start again, reporting: "Thunderbird is already running, but is not responding. The old Thunderbird process must be closed to open a new window".

W10 Resource Monitor shows that process components remain in memory, long after thunderbird.exe has terminated.

I also have a similar problem with Firefox (v66.0.3), showing the same failure to eliminate Forefox components from memory after termination, and the same failure to restart.

The only way I have found to fix the problem is to reboot. Ugh!

Recently, after terminating Thunderbird (60.6.1) on Windows 10 (v1809), it will not start again, reporting: "Thunderbird is already running, but is not responding. The old Thunderbird process must be closed to open a new window". W10 Resource Monitor shows that process components remain in memory, long after thunderbird.exe has terminated. I also have a similar problem with Firefox (v66.0.3), showing the same failure to eliminate Forefox components from memory after termination, and the same failure to restart. The only way I have found to fix the problem is to reboot. Ugh!
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Try removing the profile lock file:

http://kb.mozillazine.org/Profile_in_use#Remove_the_profile_lock_file

Works for TB and Firefox.