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Why does Firefox reset each time it's started?

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  • Last reply by cor-el

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Adblock Plus is also seemingly disabled, and I get a blank screen in the Add-ons Manager if I try to view any information about it, yet the Add-ons Manager says that it's enabled. Only after I've uninstalled and reinstalled it will it work, but it just resets again once I close and restart Firefox. I followed the instructions at http://mzl.la/Mt91fd, and when I try to delete the prefs.js file, a dialog box pops up with the message "Cannot delete prefs: The file or directory is corrupted and unreadable."

Adblock Plus is also seemingly disabled, and I get a blank screen in the Add-ons Manager if I try to view any information about it, yet the Add-ons Manager says that it's enabled. Only after I've uninstalled and reinstalled it will it work, but it just resets again once I close and restart Firefox. I followed the instructions at http://mzl.la/Mt91fd, and when I try to delete the prefs.js file, a dialog box pops up with the message "Cannot delete prefs: The file or directory is corrupted and unreadable."

Modified by Laura Brinson

Chosen solution

You can do a disk check with the chkdsk.exe program.

If you run the chkdsk.exe program from a cmd.exe Command window then you can read the response from the chkdsk.exe program.

Open a cmd.exe window:

  • Start > Run: cmd.exe <press Enter>

At the command prompt (>) type or Copy&Paste: chkdsk.exe /f /r <press Enter> (put a space before /f and /r)

If you get something like: Would you like to schedule this volume to be checked the next time the system restarts? y/n then answer the question with "Y" and close all programs and reboot the computer.

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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 check if there is a compatibility update available.

If this hasn't helped then also try to delete the addons.sqlite file.

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It's still resetting, and now the default theme is gone from the Add-ons Manager.

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Chosen Solution

You can do a disk check with the chkdsk.exe program.

If you run the chkdsk.exe program from a cmd.exe Command window then you can read the response from the chkdsk.exe program.

Open a cmd.exe window:

  • Start > Run: cmd.exe <press Enter>

At the command prompt (>) type or Copy&Paste: chkdsk.exe /f /r <press Enter> (put a space before /f and /r)

If you get something like: Would you like to schedule this volume to be checked the next time the system restarts? y/n then answer the question with "Y" and close all programs and reboot the computer.