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Add-on compatibility check won't stop. Last time it was at 14 minutes before I stopped it.

  • 6 cavab
  • 10 have this problem
  • 4 views
  • Last reply by guigs

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That's pretty much it. When I try to open Firefox, the Update window pops up and it says "Checking your add-ons for compatibility with this version of Firefox", and then "This may take a few minutes". The last time I timed it, it was at 14 minutes before I canceled it to try something else.

That's pretty much it. When I try to open Firefox, the Update window pops up and it says "Checking your add-ons for compatibility with this version of Firefox", and then "This may take a few minutes". The last time I timed it, it was at 14 minutes before I canceled it to try something else.

All Replies (6)

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Go to Mozilla.org and download the full installer

If there is still a problem, Start Firefox in Safe Mode While you are in safe mode; Firefox Options > Advanced > General. Look for and turn off Use Hardware Acceleration.

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I did download and reinstall Firefox to try to fix this; didn't work.

And I'm unable to open Firefox to change it to Safe Mode BECAUSE MY PROBLEM IS THAT FIREFOX WON'T OPEN.

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Anyway, I'm having a blast figuring out how to use Chrome and trying to remember all my bookmarks. Awesome.

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It is possible that there is a problem with the file(s) that store the extensions registry.

Delete the extensions.* files (e.g. extensions.json, extensions.sqlite, extensions.ini) and compatibility.ini in the Firefox profile folder to reset the extensions registry.

New files will be created when required.

See "Corrupt extension files":

If you see disabled or not compatible extensions in "Firefox/Tools > Add-ons > Extensions" then click the Tools button at the left end of the Search Bar to check if there is a compatibility update available.

If this hasn't helped then also delete the addons.json and addons.sqlite file.


You can also try to delete a possible user.js file and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default value.

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Try this; Start your Windows computer in safe mode. Then try the above again.

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Hi bigeasybroomsk,Firefox won't start - find solutions

These steps have worked in the past as well.

  1. Stop the Firefox process
  2. Turn off the wifi
  3. uninstall Firefox
  4. Turn wifi on
  5. Reinstall Firefox

Please make sure you are installing from http://www.mozilla.org/en-US/firefox/new/