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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.

  • 7 replies
  • 20 have this problem
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  • Last reply by sfhowes

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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.

I have to Ctl,Alt, Del to close Thunderbird.

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. I have to Ctl,Alt, Del to close Thunderbird.

Chosen solution

Do you have a profile lock file in your profile folder? If so, delete it and see if TB runs properly:

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

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Didn't work

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Hang on close Hmmm, does it occur if you use windows safe mode with networking?

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No Mat, Never been in Safe mode.

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I think I'm having the same problem (it's running but the main screen will not open). In safe mode, it does open! Does this suggest a solution?

Thanks!

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Chosen Solution

Do you have a profile lock file in your profile folder? If so, delete it and see if TB runs properly:

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