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I recently installed Thunderbird on a new Windows 8.1 computer. While trying to change the storage location of my emails to another drive the program will not o

  • 2 replies
  • 2 have this problem
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  • Last reply by Neilg211

Neilg211
Neilg211
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Thunderbird will not open and I receive the following message "Thunderbird is already running, but not responding. The old Thunderbird process must be closed to open a new window."

I have tried uninstalling and reinstalling Thunderbird but this has not fixed the problem.

Any ideas how I can fix the problem please.

Regards, Neil

Thunderbird will not open and I receive the following message "Thunderbird is already running, but not responding. The old Thunderbird process must be closed to open a new window." I have tried uninstalling and reinstalling Thunderbird but this has not fixed the problem. Any ideas how I can fix the problem please. Regards, Neil

Chosen solution

restart your computer Or Use the task manager to kill the running Thunderbird task.

If neither work, delete the parent.lock file in your profile folder.

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Matt
Matt
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Chosen Solution

restart your computer Or Use the task manager to kill the running Thunderbird task.

If neither work, delete the parent.lock file in your profile folder.

Neilg211
Neilg211 Question owner
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Thank you, the last solution to delete the parent.lock file solved the problem