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Thunderbird won't open

amy.glazer
amy.glazer
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I keep getting the following msg. on a M2 Mac Mini running Ventura: "A copy of Thunderbird is already open. Only one copy of Thunderbird can be open at a time." I've tried numerous suggested fixes with no success.

I keep getting the following msg. on a M2 Mac Mini running Ventura: "A copy of Thunderbird is already open. Only one copy of Thunderbird can be open at a time." I've tried numerous suggested fixes with no success.

All Replies (3)

sfhowes
sfhowes
  • Top 10 Contributor
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Have you tried deleting the .parentlock file?

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

TheWeaz
TheWeaz
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That has happened to me. Tried the parentlock solution and tried ending the task. Only a reboot would solve it.

conorcorderoy
conorcorderoy
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Can't delete parent.lock because Thunderbird is still running.

I live in an area where there are occasional power cuts. Every time I get a power cut Thunderbird tells me it can't open because it is already running. I do the whole %AppData% thing and try to delete parentlock, and get a message saying I can't delete parentlock because...Thunderbird is still running. So I have to uninstall Thunderbird and reinstall it. I have had to do this four times already and nobody seems to have a solution.

I can't believe I am alone in having this problem. Can't the guys at Mozilla fix this? None of my other programs/apps have this problem.

Help, please,

Conor