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Completely broken profiles

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Hello team,

I'm not sure what happened, but I was not able to open Firefox after restarting my PC. I currently run Windows 11 on a fully upgraded rig.

Up until today, I have been trouble free. Error 1: "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window."

I tried several options - and have been googling/trying several steps for a couple of hours (after each step, I restarted the PC):

1. Uninstalled and then Reinstalled a fresh copy of Mozilla 2. Attempted to use Command Lines to open Firefox https://wiki.mozilla.org/Firefox/CommandLineOptions 3. Opened Profile Manager and attempted to create a new profile - when I did this the new profile would not display in the Profile Manager, but it would display in the Profiles folder under Appdata [I tried this multiple times] 4. Deleted the profiles.ini file

After deleting the .ini file Error 2: "Your Firefox profile cannot be loaded. It may be missing or inaccessible." 1. Uninstalled and then Reinstalled a fresh copy of Mozilla 2. Opened Profile Manager and attempted to create a new profile. After following the Profile Wizard, another error pops up: "An unexpected error has prevented your changes from being saved."

I am completely stumped. I hope you can help, Sean

Hello team, I'm not sure what happened, but I was not able to open Firefox after restarting my PC. I currently run Windows 11 on a fully upgraded rig. Up until today, I have been trouble free. Error 1: "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window." I tried several options - and have been googling/trying several steps for a couple of hours (after each step, I restarted the PC): 1. Uninstalled and then Reinstalled a fresh copy of Mozilla 2. Attempted to use Command Lines to open Firefox [https://wiki.mozilla.org/Firefox/CommandLineOptions] 3. Opened Profile Manager and attempted to create a new profile - when I did this the new profile would not display in the Profile Manager, but it would display in the Profiles folder under Appdata [I tried this multiple times] 4. Deleted the profiles.ini file After deleting the .ini file Error 2: "Your Firefox profile cannot be loaded. It may be missing or inaccessible." 1. Uninstalled and then Reinstalled a fresh copy of Mozilla 2. Opened Profile Manager and attempted to create a new profile. After following the Profile Wizard, another error pops up: "An unexpected error has prevented your changes from being saved." I am completely stumped. I hope you can help, Sean

Chosen solution

See also:

Firefox would normally a new default profile when you delete profiles.ini without showing an error. The "Your Firefox profile cannot be loaded. It may be missing or inaccessible." error is actually caused by the opposite: the profiles.ini file is still there, but the xxxxxxxx.default-release profile folder referenced in the file as "Default=1" in profiles is gone (deleted).

I'm not sure in what state your profiles currently are, but if you want to start anew then you would have to find the troubling profiles.ini and remove this file. You can also possibly rename the Firefox folder.

  • C:\Users\<user>\AppData\Roaming\Mozilla\Firefox -> C:\Users\<user>\AppData\Roaming\Mozilla\FirefoxOLD
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Thanks for the suggestion - this is a clean install of Windows 11 on a new pc, so I can't roll back to 10.

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Chosen Solution

See also:

Firefox would normally a new default profile when you delete profiles.ini without showing an error. The "Your Firefox profile cannot be loaded. It may be missing or inaccessible." error is actually caused by the opposite: the profiles.ini file is still there, but the xxxxxxxx.default-release profile folder referenced in the file as "Default=1" in profiles is gone (deleted).

I'm not sure in what state your profiles currently are, but if you want to start anew then you would have to find the troubling profiles.ini and remove this file. You can also possibly rename the Firefox folder.

  • C:\Users\<user>\AppData\Roaming\Mozilla\Firefox -> C:\Users\<user>\AppData\Roaming\Mozilla\FirefoxOLD
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Thank you so much - I tried the links above and could not get it to work yesterday. The solution was to rename the Firefox folder. Really appreciate this, Firefox is my favorite browser.