Hi

When you try to copy your profile, are you certain that Firefox is closed and not running the background?

Your operating systems process manager should not show any running Firefox processes.

Thank you for your reply. Yes Firefox is closed and not running in the background. I made sure using task manager to confirm.

I also tried copying and backing up the profile as soon as I booted up my computer today, without doing anything else. No luck.

herhey99, I had a similar issue a few years ago, and if I remember it was my antivirus software that was responsible.

What worked for me was to first rename the profile folder by adding characters at the end. I then got no error messages while backing up. If you try this, don't forget to restore the original profile folder name afterwards.

If that does not work Another possible course of action is to temporarily pause your antivirus software's realtime protection, and see if this frees up the profile folder. Of course, if you try this don't forget to turn the antivirus protection back on afterwards.

Thank you for your reply TechHorse.

I did try disabling my anti virus yesterday, and it didn't work. I also tried renaming the folder as you suggested and it won't let me rename it.

I think the next thing I will try is to go into safe mode.

I was going to suggest safe mode or even doing via the cmd line. Could even use a usb stick with live linux to access and move files, but this is wee bit extreme. Simple to do, but why is Windows having this issue... It would be helpful if you show the error message

Thank you for your reply jonzn4SUSE

I just tried safe mode and it worked fine. Made a 7zip file without any problems.

The error messages I was getting when trying to archive the profile using 7zip was simply access denied. (for about 4,000 files)

When trying to copy in explorer I get an access denied you require permission from DESKTOP-(some letters and numbers)\(My username) to make changes to this file.

Going into safe mode to backup my profile will be a little bit of hassle, but as I stated earlier I only back it up about every 2 weeks, so not a big hassle.

Thank you everyone for your replies

Hello,

I am glad to hear that your problem has been resolved. If you haven't already, please select the answer that solves the problem. This will help other users with similar problems find the solution.

Thank you for contacting Mozilla Support.

I get the same issue. Profiles files simply won't copy since 141 update, even though I have full ownership.

I have just noticed that I have this problem.

For years I have been using a BAT file containing XCOPY commands to create a back of Firefox and Thunderbird on an external drive. I have never had any problems before. Because I do a daily backup and of lots of stuff, I just kick it off and leave it, so I hadn't noticed that it wasn't working. Getting loads of "Access denied" errors. Even if you use Windows Explorer to Copy/Paste, it the same. See attached image. Thunderbird still seems to be working as there are files in the backup with tonight's timestamp. The Firefox backup just creates a load of empty folders, no files. Now I haven't changed anything and I don't think there has been a windows update recently, but there have been a couple of Firefox updates. Current Firefox version is 141.0 64 bit. I'm running Windows 11 Pro. So I suspect Mozilla have changed something. Anyone from Mozilla got any answers?

Same issue here on two separate computers since Firefox 141.

I have lost permissions/rights/control over ALL subfolders and files under: C:\Users\MYUSERNAME\AppData\Local\Mozilla C:\Users\MYUSERNAME\AppData\Roaming\Mozilla

Cannot rename, copy, move or do anything with these files and I cannot figure out why. I get access denied on any attempt to do anything with these files, even when granting administrator access with UAC.

I have all the appropriate file ownership and ACLs. The local and roaming Mozilla folders and subfolders/files have full control permissions granted to SYSTEM, Administrators group, and MYUSERNAME which is also a member of Administrators group. Therefore there should be nothing to stop me copying, renaming, deleting or modifying these files.

I have checked to see if Firefox processes are running in Task Manager. They aren't.

I have used resource monitor resmon.exe to see if any other process is locking these files. Nothing.

I have used administrator elevated command prompt to try and change ownership of the files using takeown. Access denied.

I have used administrator elevated command prompt to try and change the ACLs using icacls. Access denied.

There seems to be only three ways to get access to these folders: 1) Windows safe mode. 2) Access the C drive of Computer A by granting file sharing network access to Computer B. Then Computer B can modify, copy, change etc. the files on Computer A even when the local admin user on Computer A can't. And WTF on that, BTW? 3) Uninstall Firefox completely, but then when I reinstall, the problem returns.

So the result of this is I can't backup my profile folder under ...AppData/Roaming/Mozilla/Firefox/Profiles using my daily local backup software, because access to the files is denied. Even just to copy them to another location. Can't manually copy them in Explorer, or using command line, or robocopy, or anything.

I can't use utilities like SpeedyFox to clean up and compact the database files, because access is denied.

This is very strange and a real issue. There should be absolutely no reason why I cannot have full control and access to these files. No reason I shouldn't be able to copy them for backup without having to drop into safe mode to do it. This has never been a problem until Firefox 141.

No other application data folders under /AppData/Local or /AppData/Roaming exhibit this issue. Only the Mozilla folder.

What gives? It's a mystery. It just should not be, yet it is.

To those experiencing this issue, I was wondering what happens if you try creating a new profile in a location that is outside of any Mozilla AppData folders? Does that new profile folder also get blocked from being copied etc?

If it doesn't, then one workaround for now would be to transfer the data from the original profile to the new one, and at least you wouldn't need to reboot into Windows safe mode to make a backup.

Thanks for the suggestion TechHorse. I just tried making a different profile on a different drive and it seemed to work fine. I could backup that profile no problem.

So I then erased the contents of the new profile folder, and copied the contents of my backed up profile to the new profile folder.

Tried out the profile to make sure everything was correct, and it was.

The closed Firefox and tried to backup profile and it worked no problem.

Yes, tested. Can create new profiles outside the C:\Users\USERNAME\AppData\Roaming\Mozilla folder and the newly created files and folders have the expected behavior, i.e. they can be copied/modified by users/groups with the appropriate permissions and ACLs, as expected.

So what exactly is happening that it locks up the default Mozilla folder and prevents expected authorized user access? Something about FF 141 is causing this as it's never been an issue previously.

Does anybody from Mozilla ever take any notice of these issues? For me, not being able to back up my profile is pretty serious and yet this seems to have been going on now for several months. I see no technical input form Mozilla. I see others suggesting things like changing your profile folder. You shouldn't have to do that. They have changed something and one would expect a professional approach, where they put their hand up, say we got it wrong and we are working on a fix, with an expected date. That's what i would do and I have been in software development for nearly 50 years. I'm staggered that there seems to be no ability to directly contact any form of support. All there is, is this forum.

peter222, there have been several recent threads regarding profile copying issues, for example: https://support.mozilla.org/en-US/questions/1528043 https://support.mozilla.org/en-US/questions/1528045 https://support.mozilla.org/en-US/questions/1534872

But Firefox developers might not see the threads posted on this forum. The correct place to report bugs is at Bugzilla: https://bugzilla.mozilla.org/home (assuming that this issue hasn't been reported there already)