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Help with broken install/transferring passwords from old profile

  • 2 replies
  • 1 has this problem
  • Last reply by cor-el

ryan.barthel
ryan.barthel
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My Firefox install apparently did a background update that did not complete, I get an error 'XULRunner / Error: Platform version '129.0' is not compatible...'

I did not (do not) have a profile I had logged into for that installation, but did have many passwords saved that I'd like to still be able to use if at all possible.

I have installed another instance of Firefox that is working (on platform 129.0), and am using Windows 11. I also turned off automatic updates in hopes of preventing this in the future.

The previous profile still exists in AppData/Roaming, but I don't know how/if I can connect it to the new installation I now have.

Is it possible to either fix the incomplete update or connect my old profile to this new instance so I don't have to reset all my passwords?

Thanks!

My Firefox install apparently did a background update that did not complete, I get an error 'XULRunner / Error: Platform version '129.0' is not compatible...' I did not (do not) have a profile I had logged into for that installation, but did have many passwords saved that I'd like to still be able to use if at all possible. I have installed another instance of Firefox that is working (on platform 129.0), and am using Windows 11. I also turned off automatic updates in hopes of preventing this in the future. The previous profile still exists in AppData/Roaming, but I don't know how/if I can connect it to the new installation I now have. Is it possible to either fix the incomplete update or connect my old profile to this new instance so I don't have to reset all my passwords? Thanks!

Chosen solution

Check for your profiles on the about:profiles page.

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All Replies (2)

TyDraniu
TyDraniu
  • Top 25 Contributor
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Chosen Solution

Check for your profiles on the about:profiles page.

Helpful?

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Note that the 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.

If this happens again then you can reinstall Firefox and possibly remove the Firefox program folder to ensure all files get replaced. You may have to disable security software temporarily in case the problem persists.

Reinstall Firefox:

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