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pop up message about XUL Runner platform version 129.01 is not compatible with 129.0 miniversion 129.0 maxversion 129.0

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  • 2 have this problem
  • Last reply by cor-el

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XUL Runner platform version 129.01 is not compatible with 129.0 miniversion 129.0 maxversion 129.0 When this happened at first I did not have the use of Firefox. I then went to Firefox and down downloaded Firefox and started over. Then I went to go to my bookmarks and could not find them, bummer. Now I still get this XUL Runner message ??????? email guybrochu@yahoo.com

XUL Runner platform version 129.01 is not compatible with 129.0 miniversion 129.0 maxversion 129.0 When this happened at first I did not have the use of Firefox. I then went to Firefox and down downloaded Firefox and started over. Then I went to go to my bookmarks and could not find them, bummer. Now I still get this XUL Runner message ??????? email guybrochu@yahoo.com

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An error message like XPCOM missing or about platform version or entry points not found can happen because of a failed Firefox update that left you with a mixture of old and updated files in the Firefox installation folder. This can happen in case security software was keeping a handle of some of the files in the Firefox program folder preventing Firefox from replacing all the files.

You need to reinstall Firefox and possibly remove the Firefox program folder to ensure that all files are replaced. You may have to disable security software temporarily in case the problem persists.

Reinstall Firefox:

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