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can't download addons even manually

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  • 1 has this problem
  • 1 view
  • Last reply by cor-el

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Adblock plus deleted itself for some reason tried to download it again download gets stuck with at 100% and never finishes tried to download other apps and the same thing happens I try to download it from other sites and it still won't work I save it as an xpi file and try to install it manually, picking the file and clicking "open" doesn't cause the option to install to pop up

now what do I do?

Adblock plus deleted itself for some reason tried to download it again download gets stuck with at 100% and never finishes tried to download other apps and the same thing happens I try to download it from other sites and it still won't work I save it as an xpi file and try to install it manually, picking the file and clicking "open" doesn't cause the option to install to pop up now what do I do?

All Replies (3)

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What security software do you have?

It is possible that security software (anti-virus, firewall) is causing problems. Try to disable security software temporarily to see if that makes a difference.

Can you download and save the xpi file to your desktop?

If that works then try to drag the file in a Firefox window.

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cor-el said

What security software do you have? It is possible that security software (anti-virus, firewall) is causing problems. Try to disable security software temporarily to see if that makes a difference. Can you download and save the xpi file to your desktop? If that works then try to drag the file in a Firefox window.


Tried all of that, didn't work.

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Can you install an extension if you start Firefox in Safe Mode?

Try to start Firefox in Safe Mode by holding down the Shift (Mac: Options) key to see if that has effect.

It is possible that there is a problem with files in the profile folder that store the extensions registry.

Delete the extensions.* files (e.g. extensions.json, extensions.ini, extensions.sqlite) 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 "3-bar Menu button/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 didn't help then delete Add-ons.json and possibly prefs.js in case there is a problem with preferences.

You can use this button to go to the current Firefox profile folder:


Create a new profile as a test to check if your current profile is causing the problem.

See "Creating a profile":

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.

Modified by cor-el