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Thunderbird won't close properly and I can't restart the program. Any new ideas?

  • 1 reply
  • 2 have this problem
  • 2 views
  • Last reply by Toad-Hall

charmonar
charmonar
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I keep getting the error, "Thunderbird is already running, but is not responding. To open a new window, you must first close the existing Thunderbird process, or restart your system", when I close and then later try to restart Thunderbird. The only fix is to either open Task Manager and kill Thunderbird that way, or to restart the computer.

I have searched the knowledge base on Mozilla online and have already deleted the Lock files from the Profile directory but this did not fix the problem. I also already went into Safe Mode and tried closing and restarting the program there. The problem does not occur in Safe Mode. Only in regular operating mode. I am running Windows 7 64 bit.

Any help would be greatly appreciated.

I keep getting the error, "Thunderbird is already running, but is not responding. To open a new window, you must first close the existing Thunderbird process, or restart your system", when I close and then later try to restart Thunderbird. The only fix is to either open Task Manager and kill Thunderbird that way, or to restart the computer. I have searched the knowledge base on Mozilla online and have already deleted the Lock files from the Profile directory but this did not fix the problem. I also already went into Safe Mode and tried closing and restarting the program there. The problem does not occur in Safe Mode. Only in regular operating mode. I am running Windows 7 64 bit. Any help would be greatly appreciated.

All Replies (1)

Toad-Hall
Toad-Hall
  • Top 10 Contributor
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If you tried Thunderbird safe mode: Help > restart with addons disabled

and it worked ok, this means that one of your addons is causing a conflict. You will need to enable each addon extension, one at a time and test to see which one causes the issue. Maybe an addon needs to be updated.

Modified by Toad-Hall