AskVG

[Firefox Fix] All Existing Add-ons got Disabled, Can’t Install New Extensions

- Last updated on by

PROBLEM SYMPTOM:

You use Mozilla Firefox web browser in your computer. When you opened Firefox, you found that suddenly all existing/previously installed add-ons disabled automatically. Those add-ons or extensions were working fine in past but now all add-ons are disabled and Firefox is showing “One or more installed add-ons cannot to be verified and have been disabled” notification message at the top. When you open Add-ons Manager (about:addons) page in Firefox, it shows all installed add-ons disabled with “could not be verified for use in Firefox and has been disabled” message for all disabled add-ons/extensions. It also shows “Find a Replacement” button to find an alternative for the disabled extension along with “Remove” button to uninstall the disabled extension. So you can’t use any add-on/extension in Firefox.

Also if you try to install a new extension from official Firefox add-ons website (addons.mozilla.org), you get following error messages:

Download failed. Please check your connection.

Advertisement

The add-on could not be downloaded because of a connection failure.

The add-on downloaded from this site could not be installed because it appears to be corrupt.

So you are also unable to install any new add-on/extension in Mozilla Firefox.

PROBLEM SOLUTIONS:

SOLUTION 1:

By default, Mozilla Firefox checks for verified signature on installed add-ons as well as whenever you want to install a new add-on or extension, this is called add-on signature enforcement. You can disable this feature and install desired add-on/extension forcefully without any issue. It’ll also re-enable existing add-ons which got disabled automatically.

To disable this feature, you’ll need to set xpinstall.signatures.required preference to false on about:config page.

Disable_Addon_Signature_Check_Firefox.png

Advertisement

Following tutorial contains step-by-step procedure to disable add-on signature enforcement:

[Firefox Tips] Disable Add-on Signature Enforcement

After disabling this feature, try to install an add-on and it’ll install without any problem. Also all your previously installed add-ons/extensions will be enabled successfully.

SOLUTION 2:

1. Open official Firefox add-ons website (addons.mozilla.org) and go to the desired add-on/extension page which you want to install.

2. Right-click on “+ Add to Firefox” button and select “Save Link As” option. It’ll download the .XPI file of the extension in your downloads folder.

3. Now type about:debugging in Firefox address bar and press Enter. It’ll open Add-ons Debugging page.

4. Now click on “Load Temporary Add-on” button, browse to the downloads folder and select .XPI file of your desired extension which you saved in step 2.

Load_Temporary_Addon_Firefox_Debugging.png

That’s it. It’ll immediately install the add-on/extension without any error message.

NOTE to Re-Enable Existing Add-ons/Extensions: The .XPI file of your existing add-ons/extensions are stored in “Extensions” folder inside your Firefox profile folder. You can select the XPI file of all installed extensions one by one in step 4 to re-enable disabled extensions in Firefox. To learn where is your Firefox profile folder located and how to open it, following tutorial will help you:

All About Mozilla Firefox Profile Folder and Configuration Files

Also Check:

Fix Add-ons Disabled Problem in Mozilla Firefox (47-65) Older Versions

Published in: Mozilla Firefox, Troubleshooting Guides

About the author: Vishal Gupta (also known as VG) has been awarded with Microsoft MVP (Most Valuable Professional) award. He holds Masters degree in Computer Applications (MCA). He has written several tech articles for popular newspapers and magazines and has also appeared in tech shows on various TV channels.

You are here: Home » Mozilla Firefox » [Firefox Fix] All Existing Add-ons got Disabled, Can’t Install New Extensions

Comments

NOTE: Older comments have been removed to reduce database overhead.

  1. The overriding Add-on signing solution only works for Nightly, Dev and Android users since from Firefox 48 onward Add-on signing can not be overridden.

  2. According to the latest announcement from Mozilla:

    We rolled-out a fix for release, beta and nightly users on Desktop. The fix will be automatically applied in the background within the next few hours, you don’t need to take active steps.

    In order to be able to provide this fix on short notice, we are using the Studies system. You can check if you have studies enabled by going to Firefox Preferences -> Privacy & Security -> Allow Firefox to install and run studies.

    You can disable studies again after your add-ons have been re-enabled.

    We are working on a general fix that doesn’t need to rely on this.

  3. they have a RC: 66.0.4

    ftp .mozilla.org/pub/firefox/candidates/66.0.4-candidates/build1/win64/en-US/Firefox%20Setup%2066.0.4.exe

  4. First solution not working on older firefox, however solution 2 works fine.

    Thank you for your work.

  5. I cannot think you enough for this tutorial. It came at the right time. Right after reading it, I had a message at the top of FF’s window with regard to this problem and all my add-ons were gone.

    Like @martin above, the first solution is not working, but the second one does the job seamlessly.

    Big thank you!

  6. Correction of my typo in previous message:
    “I cannot think you” should have read ” I cannot thank you”

    Too bad you don’t have an “Edit” button for this kind of mistake. Cheers!

  7. thank you so much…i was searching for the solution the whole day and finally with both of these solutions it worked perfectly…thanks <3

  8. Thanks a million for this coverage.
    When all your passwords are unavailable because the Firefox add-on is disabled it a disaster!
    The Firefox fix did the trick and restored all my add-ons.
    Thanks so much for the coverage.

    B

  9. Unfortunately the load temporary addon thing only works as long as you don’t close and reopen firefox. It’s been the best solution so far thouhg, nothing mozilla has written ever helped.

  13. For me, the temporary (permanent?) fix was discussed on another forum, I forget where, but the person said that if you are using Windows, you have to go into the app’s Properties window, look for compatability mode, and set it to Windows 7 {by default, Firefox has it set for Windows 8???).

    This allows not only for the addons to be reactivated, but also gives you back the ability to download addons from the Addons page again and not have that “connection fail” message.

    I have yet to hit the 24-hour reset again for this bug to see it as a permanent solution yet, but I hope this helps.

  14. This seems to be an ongoing issue accompanying Firefox updates. Now (May 2019) fix 2 from the article seems to work (I didn’t try the first), if temporarily (it does load the add-ons as temporary, as the article says), if accompanied by such messages being displayed on about:debugging, as “Reading manifest: Error processing storage: An unexpected property was found in the WebExtension manifest.” and/or “Reading manifest: Error processing update_url: An unexpected property was found in the WebExtension manifest.” Raul F. Calixto II’s fix does not appear to work.

  15. Instead of installing each addons one by one and if you haven’t received the fix distributed via the studies, install this fix (it’s the same fix, in downloadable xpi form) using the method for addons. fixed my situationđź‘Ť

    storage.googleapis.com/moz-fx-normandy-prod-addons/extensions/hotfix-update-xpi-intermediate%40mozilla.com-1.0.2-signed.xpi

  16. This immediately solved my problem and restored my previously disabled extensions and add ons. I used solution 1. Thank you.

  17. Mozilla has released Firefox 66.0.4 version which fixes the add-ons disabled issue:

    mozilla.org/en-US/firefox/66.0.4/releasenotes/

  20. I just got this issue yesterday

    Had to sync, uninstall, erase my profile folder and reinstall

    :-/

  21. for now Both solutions are working and im on 56.0 64bit. My deepest Thanks for the info.

  22. permanently fix for older firefox:
    reddit.com/r/firefox/comments/bkspmk/addons_fix_for_5602_older/

  23. I use FF v61.0.2 and have the same problem. I won’t update to new FF version because of personal projects in my computer (need older version of FireFox). Why my add-ons are also disabled if I don’t have latest FF build ?

  24. Mozilla has released Firefox 66.0.5 version which fixes the add-ons disabled issue:

    mozilla.org/en-US/firefox/66.0.5/releasenotes/

Leave a Comment

Your email address will not be published. Required fields are marked *

NOTE: Your comment may not appear immediately. It'll become visible once we approve it.