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Am not able to install any add-ons in Firefox 11 and the suggested fixes here don't seem to work. Any suggestions?

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  • Last reply by cor-el

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Installed Firefox 11 and no add-ons display. Tried to install Autofill Forms and I get the message "There was an error installing AutoFill Forms. Try Again" Same for any other add-on. Also running Norton 360V6 and can't even see Norton Toolbar. Have uninstalled and reinstalled both Firefox and 360 (the latter using Norton Removal Tool). Do not have this problem with Internet Explorer or with Firefox 11 on my other computers. Just this one. Plugins from an earlier version of Firefox show up, but not any Add-Ons.

Installed Firefox 11 and no add-ons display. Tried to install Autofill Forms and I get the message "There was an error installing AutoFill Forms. Try Again" Same for any other add-on. Also running Norton 360V6 and can't even see Norton Toolbar. Have uninstalled and reinstalled both Firefox and 360 (the latter using Norton Removal Tool). Do not have this problem with Internet Explorer or with Firefox 11 on my other computers. Just this one. Plugins from an earlier version of Firefox show up, but not any Add-Ons.

Chosen solution

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

Delete the files extensions.* (e.g. extensions.sqlite, extensions.ini, extensions.cache) 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, not compatible, extensions in "Tools > Add-ons > Extensions" then click the Tools button at the left side of the Search Bar (or click the "Find Updates" button in older Firefox versions) to do a compatibility check or see if there is a compatibility update available.

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Maybe try the Troubleshoot and diagnose Firefox problems article first?

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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 files extensions.* (e.g. extensions.sqlite, extensions.ini, extensions.cache) 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, not compatible, extensions in "Tools > Add-ons > Extensions" then click the Tools button at the left side of the Search Bar (or click the "Find Updates" button in older Firefox versions) to do a compatibility check or see if there is a compatibility update available.