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Can't open Firefox - error re "platform version '120.0.1'

  • 3 replies
  • 25 have this problem
  • 123 views
  • Last reply by Chris

Hello,

Clicking to open Firefox gives me the following error message:

Error. Platform version '120.0.1' is not compatible with miniVersion >= 120.0 maxVersion <= 120.0

Can't open firefox! I'm running Windows 11 version 10.0.22631 Build 22631

Thanks! Julie

Hello, Clicking to open Firefox gives me the following error message: Error. Platform version '120.0.1' is not compatible with miniVersion >= 120.0 maxVersion <= 120.0 Can't open firefox! I'm running Windows 11 version 10.0.22631 Build 22631 Thanks! Julie

Chosen solution

Hello. It seems that you have a mixture of old and new files. I suggest that you remove Firefox and reinstall it. You may want to consider a 'custom' installation.

https://support.mozilla.org/en-US/kb/uninstall-firefox-from-your-computer https://support.mozilla.org/en-US/kb/custom-installation-firefox-on-windows

Read this answer in context 👍 3

All Replies (3)

Chosen Solution

Hello. It seems that you have a mixture of old and new files. I suggest that you remove Firefox and reinstall it. You may want to consider a 'custom' installation.

https://support.mozilla.org/en-US/kb/uninstall-firefox-from-your-computer https://support.mozilla.org/en-US/kb/custom-installation-firefox-on-windows

Thank you! Odd that it suddenly happened.

Appreciate your suggestion.

Terry schrieb

Hello. It seems that you have a mixture of old and new files. I suggest that you remove Firefox and reinstall it. You may want to consider a 'custom' installation. https://support.mozilla.org/en-US/kb/uninstall-firefox-from-your-computer https://support.mozilla.org/en-US/kb/custom-installation-firefox-on-windows

I had the same problem. Reinstalling was the solution. Thank You!!!