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Unable to enable extensions

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  • Last reply by FredMcD

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Hello, Every time I try to install an extension on Firefox I can't keep the extensions that I want enabled after I open Firefox. For example, I have tried installing the extension Firefox Test Pilot after installing it asks me to restart Firefox, I click restart Firefox of course. However this is where the problem comes in, after it restarts it then opens up an "Install Add-on" page for every extension I have installed and asks me this: Another program on your computer would like to modify Firefox with the following add-on: Test Pilot 0.9.0-dev-2ac545a By Mozilla then where the file is located on my computer then Install add-ons only from authors whom your trust. Then a check box and the follow Allow this installation. I check the box press continue and sometimes they ask to restart Firefox and sometimes the window just closes. Regardless of what it ask me after I restart Firefox close it and open it again it replays the same loop and opens a "Install Add-on" page for every extension I have installed. This in turn disables all of my extensions every time I close and reopen Firefox. I have tried refreshing or resetting Firefox and have even uninstalled and reinstalled Firefox multiple time with out any success. Please help! Thank you.

Hello, Every time I try to install an extension on Firefox I can't keep the extensions that I want enabled after I open Firefox. For example, I have tried installing the extension Firefox Test Pilot after installing it asks me to restart Firefox, I click restart Firefox of course. However this is where the problem comes in, after it restarts it then opens up an "Install Add-on" page for every extension I have installed and asks me this: Another program on your computer would like to modify Firefox with the following add-on: Test Pilot 0.9.0-dev-2ac545a By Mozilla then where the file is located on my computer then Install add-ons only from authors whom your trust. Then a check box and the follow Allow this installation. I check the box press continue and sometimes they ask to restart Firefox and sometimes the window just closes. Regardless of what it ask me after I restart Firefox close it and open it again it replays the same loop and opens a "Install Add-on" page for every extension I have installed. This in turn disables all of my extensions every time I close and reopen Firefox. I have tried refreshing or resetting Firefox and have even uninstalled and reinstalled Firefox multiple time with out any success. Please help! Thank you.

Chosen solution

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

Type about:support in the address bar and press enter.

Under the page logo on the left side, you will see Application Basics. Under this find Profile Folder. To its right press the button Show Folder. This will open your file browser to the current Firefox profile. Now Close Firefox.

Delete all extensions files and compatibility.ini in the Firefox profile folder to reset the extensions registry.

New files will be created when required.

After, restart Firefox.

See "Corrupt extension files":


You will have to approve the updating one last time.

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Chosen Solution

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

Type about:support in the address bar and press enter.

Under the page logo on the left side, you will see Application Basics. Under this find Profile Folder. To its right press the button Show Folder. This will open your file browser to the current Firefox profile. Now Close Firefox.

Delete all extensions files and compatibility.ini in the Firefox profile folder to reset the extensions registry.

New files will be created when required.

After, restart Firefox.

See "Corrupt extension files":


You will have to approve the updating one last time.