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Firefox update won't finish checking add ons.

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  • Last reply by drkenrich

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When I started Firefox this AM the "Checking Compatibility of Add-ons" box comes up, but it won't finish. Clicking on the cancel button does nothing either. I have tried uninstalling Firefox, restarting and installing to no avail.

When I started Firefox this AM the "Checking Compatibility of Add-ons" box comes up, but it won't finish. Clicking on the cancel button does nothing either. I have tried uninstalling Firefox, restarting and installing to no avail.

Chosen solution

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 check for problems with the preferences and 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.*http://kb.mozillazine.org/Preferences_not_saved

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Chosen Solution

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 check for problems with the preferences and 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.*http://kb.mozillazine.org/Preferences_not_saved

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I had this problem...again. I've tried all the solutions in this forum with minimal success. But I FOUND A SOLUTION!!

I reinstalled FF, tried fixing about:config, deleted the extensions.* files, turned off auto update on both FF and the add-ons, clicked on change add-ons to manually update, and then even went in and actually did change each one to OFF for updates. Nothing worked.

It was operator error (me). I like to do things quick so I install FF (V 24), then I open tabs for all the add-ons I know I want, then install all of them before I restart.

This time I started with a clean install, opened my add-on tabs, but installed each one, then restarted, before installing the next one.

It worked!!