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Can't install add-ons on my Macbook because firefox "cannot modify the needed file" !!

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Can't install add-ons on my Macbook because firefox "cannot modify the needed file" !!

I am not sure how to use terminal and commands in the same. Help with the same would be greatly appreciated.

1 ACCEPTED SOLUTION

Accepted Solutions
New Contributor

Re: Can't install add-ons on my Macbook because firefox "cannot modify the needed file" !!

You can try resetting the account by using the link :

http://support.mozilla.org/en-US/kb/reset-firefox-easily-fix-most-problems

Hope this helps.

8 REPLIES
Legendary Contributor

Re: Can't install add-ons on my Macbook because firefox "cannot modify the needed file" !!

Hi diveshsareen

see : Command line arguments - For Linux and Mac OS X users

try cor-el reply in the next link : https://support.mozilla.org/en-US/questions/923286


thank you

Site Moderator

Re: Can't install add-ons on my Macbook because firefox "cannot modify the needed file" !!

You get that message if the extension needs to be unpacked to run properly because it want to make changes or save data in its extension folder.
The normal way is to copy the extensions XPI file to its extensions folder without unpacking all files.

Which extension(s) give you that error message?

New Contributor

Re: Can't install add-ons on my Macbook because firefox "cannot modify the needed file" !!

Hi Guys, I am having issue installing firebug and web developer. Is there an easy fix / step by step guide or video I can refer to please ?? Thanks.

Site Moderator

Re: Can't install add-ons on my Macbook because firefox "cannot modify the needed file" !!

Try to set the Boolean pref extensions.alwaysUnpack to true on the about:config page.

New Contributor

Re: Can't install add-ons on my Macbook because firefox "cannot modify the needed file" !!

Hey,

I'm having the exact same issue, except I'm on OSX 10.8.2 and FF 16.0.1.

I can't install any extensions. If I try via Tools -> Add Ons, I get the error "There was an error installing <extension-name>". If I try via the addons.mozilla.org site I get the "can't modify file" error msg.

I have changed extensions.alwaysUnpack to TRUE, but there is no change.

Any help would be greatly appreciated.

New Contributor

Re: Can't install add-ons on my Macbook because firefox "cannot modify the needed file" !!

You can try resetting the account by using the link :

http://support.mozilla.org/en-US/kb/reset-firefox-easily-fix-most-problems

Hope this helps.

New Contributor

Re: Can't install add-ons on my Macbook because firefox "cannot modify the needed file" !!

I mean try resetting firefox as this resolved the issue for me.

New Contributor

Re: Can't install add-ons on my Macbook because firefox "cannot modify the needed file" !!

That worked perfect, I now have Firebug.

Thank you