Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Denne tråden ble arkivert. Still et nytt spørsmål dersom du trenger hjelp.

Add-on efforts fail with a message that it couldn't be done because Firefof could not modigy some file; forums are no help--I am not a computer wizard and they are greek to me. HELP!

  • 1 svar
  • 4 har dette problemet
  • 3 views
  • Siste svar av cor-el

emcms11
emcms11
more options

Sorry about the typos--Firefox and modify. The message I always get is{X} add-on "could not be installed because Firefox cannot modify the needed file". Just Google that quote and you'll get many complaints about this on your Forum, none of which is at all understandable to me. I am a longtime Firefox user, with Mac OSX 10.6.8 Macpro. Your version is 5.0.1

Please tell me how to get addons to be installed, in simple English.

Sorry about the typos--Firefo'''x''' and modi'''f'''y. The message I always get is{X} add-on "could not be installed because Firefox cannot modify the needed file". Just Google that quote and you'll get many complaints about this on your Forum, none of which is at all understandable to me. I am a longtime Firefox user, with Mac OSX 10.6.8 Macpro. Your version is 5.0.1 Please tell me how to get addons to be installed, in simple English.

All Replies (1)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
more options

This can be a problem with the file(s) that store the extensions registry.

Delete the files extensions.* (extensions.sqlite, extensions.ini, extensions.cache, extensions.rdf) 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 an update.