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Update 27.0.1 - add-on compatibility never progresses, can not install.

  • 4 tontu
  • 8 am na jafe-jafe bii
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  • i mujjee tontu mooy Kamakani

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I recently attempted to open Firefox and found out it had updated. Firefox never opened, the only window that opened was the Firefox Update window at the "Checking Compatibility of Add-ons" stage. The update never progressed past this point. Hours went by and still nothing.

This morning I decided to try uninstalling and reinstalling Firefox. It stops progressing at the same point as when it updated.

I receive no errors and there are no crash reports. Any help would be appreciated.

I recently attempted to open Firefox and found out it had updated. Firefox never opened, the only window that opened was the Firefox Update window at the "Checking Compatibility of Add-ons" stage. The update never progressed past this point. Hours went by and still nothing. This morning I decided to try uninstalling and reinstalling Firefox. It stops progressing at the same point as when it updated. I receive no errors and there are no crash reports. Any help would be appreciated.

Saafara biñ tànn

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.


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 including prefs set via user.js and prefs that are no longer supported in the current Firefox release.

Jàng tontu lii ci fi mu bokk 👍 4

All Replies (4)

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See if you can Start Firefox in Safe Mode While you are in safe mode; Firefox Options > Advanced > General. Look for and turn off Use Hardware Acceleration.

Clear the Cache Firefox/Tools > Options > Advanced > Network > Cached Web Content: "Clear Now"

(Removed bad link to old versions of software) LAST RESORT ! ! Reset Firefox

user633449 moo ko soppali ci

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Please don't follow Fred's suggestions above, they won't help in this situation.

Go to www.getfirefox.com, and download Firefox 27.0.1, install it, and then if you get the checking compatibility window again, try to exit it or press Cancel.

The other thing to try is to check your Firewall settings:

Configure firewalls so that Firefox can access the Internet

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Saafara yiñ Tànn

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.


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 including prefs set via user.js and prefs that are no longer supported in the current Firefox release.

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Thanks for all the responses and tips. after trying them all, it was resolved after making the changes cor-el suggested.

thanks again.