Firefox cannot modify the needed file

[Tim_Olaguna]

I am extremely frustrated here and desperately need help. Today I downloaded and installed a brand new clean version of Firefox 10.0.1. I am running it on a PC with 8 GB RAM on a 64 bit version of Windows 7, Home Premium.

I am the Administrator of my system. I have previously had no problems running Firefox on my system. But now I absolutely cannot add any extensions or themes to Firefox. The message I receive on every attempt says,

"[Name of extension or theme] for Firefox could not be installed because Firefox cannot modify the needed file."

I have tried running Firefox in safe mode. No dice. I get the same responses. I have searched this forum and Google to no avail. Some people have had some problems like this with specific applications and have found solutions, but no one seems to have had a problem with all extensions or themes. Trying a new clean profile has not helped. It might be helpful if Firefox identified what the needed file is, but it does not.

Does anybody have any ideas as to what I should try next to get Firefox running as I am used to?

[KWierso]

Go to Help - Troubleshooting Information, and click the button that says "Open containing folder" (or "Show folder". Not sure when that got changed around).

Close Firefox after that other window pops up.

Give Firefox time to fully shut down. In the window that pops up, cut both "addons.sqlite" and "extensions.sqlite", and paste them to somewhere else for safekeeping (like the desktop or My Documents).

Try starting Firefox back up (you'll probably have it check your extensions again and offer to have you manually enable any 3rd-party extensions that are installed on your system), then try installing some other extension again.

[Tim_Olaguna]

Go to Help - Troubleshooting Information, and click the button that says "Open containing folder" (or "Show folder". Not sure when that got changed around).

Close Firefox after that other window pops up.

Give Firefox time to fully shut down. In the window that pops up, cut both "addons.sqlite" and "extensions.sqlite", and paste them to somewhere else for safekeeping (like the desktop or My Documents).

Try starting Firefox back up (you'll probably have it check your extensions again and offer to have you manually enable any 3rd-party extensions that are installed on your system), then try installing some other extension again.

Thank you, KWierso, for your time and suggestion. Unfortunately, it did not work. I followed your directions several times, but the problem persists. Here is a sampling of the error messages I am seeing in the extensions.log file:

2012-02-11 17:55:10 ERROR addons.xpi: SQL error 14: unable to open database file at resource:///modules/XPIProvider.jsm:3903
2012-02-11 17:55:10 ERROR addons.xpi: Failed to add add-on {972ce4c6-7e08-4474-a285-3208198ce6fd} in app-global to database: [Exception... "Component returned failure code: 0x80520015 (NS_ERROR_FILE_ACCESS_DENIED) [mozIStorageStatement.execute]" nsresult: "0x80520015 (NS_ERROR_FILE_ACCESS_DENIED)" location: "JS frame :: resource:///modules/XPIProvider.jsm :: executeStatement :: line 3925" data: no] at resource:///modules/XPIProvider.jsm:3925
2012-02-11 17:55:10 ERROR addons.xpi: SQL error 14: unable to open database file at resource:///modules/XPIProvider.jsm:3903

[Anonymosity]

Try these pages for ideas:
http://kb.mozillazine.org/Unable_to_ins ... _-_Firefox
https://support.mozilla.com/kb/Troubles ... and+themes

[Guest]

Thanks so much for your time, but I've been through both of those pages and they are classic Firefox no-help. The second link is way out of date, continually referring to possible solutions which may have been applicable to die-hard users of WinXP but of no use to us using Win 7 64 bit (as specified in my original post). Furthermore, they continually assume the problem is likely caused by incompatible themes or extensions but, again as I noted, I am working from a new install of Firefox 10.0.1 and have not been able to install ANY extensions or themes, including ones which might possibly cause conflicts.

[Mihir Mehta]

I faced the same issue and found the cause of this issue is that the path of my default profile folder was way too long.

All I did was to create a new profile pointing to a simple and a shorter path and delete my old profile and it solved the issue. I am now able to install new addons on Firefox 12

Please refer to this to create a new profile and delete the existing one. Let me know if this helps!

http://support.mozilla.org/en-US/kb/Man ... -a-profile

Cheers,
Mihir
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