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XUL Runner Error

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  • 1 has this problem
  • 4 views
  • Last reply by christ1

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My computer went through an automatic Windows update last night. I am running Windows 10 because the PC does not have the minimum requirements for Windows 11. When I signed into Thunderbird this morning, there was an automatic Thunderbird update.

Now I cannot get on to Thunderbird. I get the following error message: XULRunner Error - Platform version 91.4.1 is not compatible with minversion >=91.5.0 maxversion<=91.5.0

All my email files and address books are stored locally and I have no access to them. What can I do to restore access to Thunderbird?

My computer went through an automatic Windows update last night. I am running Windows 10 because the PC does not have the minimum requirements for Windows 11. When I signed into Thunderbird this morning, there was an automatic Thunderbird update. Now I cannot get on to Thunderbird. I get the following error message: XULRunner Error - Platform version 91.4.1 is not compatible with minversion >=91.5.0 maxversion<=91.5.0 All my email files and address books are stored locally and I have no access to them. What can I do to restore access to Thunderbird?

All Replies (1)

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Close Thunderbird. Download the 91.5.0 installer from https://www.thunderbird.net/ and run it. Start Thunderbird.