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Error Message When Trying to Open the App

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  • Last reply by Toad-Hall

ashe.london123
ashe.london123
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Hello,

I am trying to open the Thuderbird app on my Windows desktop PC, however I keep getting the following error message before the program even opens:

``Thunderbird is already running, but is not responding. The old Thunderbird process must be closed to open a new window.``

I have tried closing the background processes using alt, ctrl, delete. I also tried uninstalling, and then reinstalling the Thunderbird app from the setup file. I`ve also tried deleting the setup file, and installing it again fresh from the website.

Every time, the same error message appears and I cannot open it.

How can I solve this problem?

Thank you so much.

Hello, I am trying to open the Thuderbird app on my Windows desktop PC, however I keep getting the following error message before the program even opens: '''``Thunderbird is already running, but is not responding. The old Thunderbird process must be closed to open a new window.``''' I have tried closing the background processes using alt, ctrl, delete. I also tried uninstalling, and then reinstalling the Thunderbird app from the setup file. I`ve also tried deleting the setup file, and installing it again fresh from the website. Every time, the same error message appears and I cannot open it. How can I solve this problem? Thank you so much.

All Replies (1)

Toad-Hall
Toad-Hall
  • Top 25 Contributor
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Maybe it's possible Thunderbird had not completely updated all background processes before computer was shut down, so it still has a setting which the program reads as 'I'm already running'.

Try this:

In bottom search type: %Appdata% - see image below as guide

  • select the %Appdata% file folder
  • select 'Roaming' folder
  • select 'Thunderbird' folder
  • Select 'Profiles' folder
  • select 'the profile name ' folder
  • delete this file : parent.lock

When you Start thunderbird that file will get recreated which is normal.