Firefox Community Forum

I got so frustrated with not being able to reinstall Firefox because I kept getting the error message "Your Firefox profile cannot be loaded. It may be missing or inaccessible". So I deleted all the profiles after copying them to an external hard drive. Then I copied the file ending in.test from the Old Firefox data folder on my desktop to the AppData/Roaming/Mozilla/Firefox/ profile. Then I copied the biggest file ending in .default from the backed up Local profiles to the AppData/Local/Mozilla/Firefox/ profile. It doesn't matter if I delete or keep the Old Firefox data folder on my desktop, I still get the Profile Missing error message. What can I do, so my laptop would appear as if it had been powered up straight out of the box and never had Firefox initially installed or what do I do with my profiles to make them accessible?

Hello, I’m having trouble getting Firefox to work properly on my computer. During installation, the setup process becomes very slow, and once I manage to install it, Firefox hangs or becomes unresponsive within a few seconds after launching.

My system details:

Operating System: Windows 10 64-bit

What I’ve tried so far:

Reinstalling Firefox Running in Safe Mode Clearing profile data Disabling antivirus temporarily

None of these steps solved the problem. There are no specific error messages — the browser just freezes, and I have to close it via Task Manager.

PLEASE READ UNTIL THE END So, a few months ago I reinstalled Windows on my laptop because I had some bugs. After the OOBE was completed, I set it up and installed Chrome. However, when I tried to log in, the app suddenly force closed and could no longer be opened. So, I switched to Firefox. Everything was running fine. But now (06/26/2025), while I was using Firefox, it suddenly force closed (this is the first time it has force closed on me). I clicked twice on the desktop but it also didn't work, I'm confused about what to do, I absolutely don't want to use Microsoft Edge. When I tried to spam the Firefox icon on the taskbar while opening the task manager, crashhelper.exe suddenly appeared many times, I tried to delete those exe files but it had no effect, so I restored them back to their directory. I'm really confused whether my laptop is broken or if there's a bug in the Windows software? So that's it and thank you.

CCleaner automatic upgrade to "ccleaner 7" killed Firefox! No other changes to the SW or machine. This computer works great every day. Fully up to date with Microsoft. The "upgrade" that I did not ask for, lost my license and switched me to the "free version of CCleaner. I uninstalled it and started over from CCleaner website. Worked fine with old version. It upgraded itself again and now Firefox is dead. Microsoft Edge does open. I never use this. Thanks

This is the message that pops up when I try to open Firefox: [Window Title] C:\Users\Kurt\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\TaskBar\Firefox.lnk

[Content] Windows cannot find 'C:\Users\Kurt\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\TaskBar\Firefox.lnk'. Make sure you typed the name correctly, and then try again.

[OK]

My Surface Laptop 7 w/ SnapDragon Elite's Firefox installation started crashing this morning immediately after rebooting to complete some Windows updates. I have attempted starting Firefox in Maintenance mode, Uninstalled and reinstalled and I still get the crash reporter. Refreshing Firefox at the uninstall process does not fix it.

I'm running Windows 11 Enterprise edition, fully patched w/ Firefox 146.0.

The 4 Windows updates that were installed:

Uninstalled KB5072033 Uninstalled KB5070311 Cannot be uninstalled KB5072641 Cannot be uninstalled KB5071142

Still didn't fix the problem.

These are the recent crash reports:

Crash ID: bp-8ec5b63c-4408-437c-b9bb-f4d5b0251213 Crash ID: bp-ce396463-0a75-46b6-8131-33cce0251213 Crash ID: bp-ea0b59dd-1cee-48da-957e-949120251213 Crash ID: bp-f9342e01-1a55-4387-af6d-3b8ef0251213

Any help is appreciated!

In my org - ever since the release of Firefox 146 - each time an update is rolled out on a WIndows 11 endpoint - Firefox is no longer able to launch.

This is resolved by uninstalling and reinstalling the client. We've had no issues with the ESR release in my testing.

What changed? Anyone else experiencing this?

I had our security team take a look at the antivirus - they've confirmed we aren't blocking Firefox and they did not see any block reports.

No relevant policy changes have gone through around the time of the incident. Initially I suspected users were installing Firefox ESR from the Company Portal alongside the standard release - but confirmed this is not the case. Also ruled out browser extensions - error persisted across a config without any extensions.

Please let me know if there is troubleshooting info I can collect. I included info from my own browser, but I reinstalled on the 27th and it has been working since. However, it has broke specifically on the days new releases have come out.

Thank you for any suggestions!

When I try to run firefox 141.0 (Linux x64) I get:

libxul.so: undefined symbol: gdk_wayland_device_get_wl_seat Couldn't load XPCOM.

Is there a way to fix this?

I'm using Slackware 14.2.

Summary - Firefox crashes repeatedly. yesterday, I decided to switch to Firefox after using Chrome for a while. it worked fine and I synced my data from Chrome. today, at some point I noticed Firefox is no longer open in my taskbar. I decided to reopen it - it crashed. since that moment it has never worked again. I tried launching it in safe mode (firefox.exe -safe-mode), didn't work. tried reinstalling it, didn't work. manually deleted the files from C:\Program Files and AppData, installed Firefox again, didn't work. reinstalled gpu drivers, didn't work. sfc /scannow-ed, you guessed it - still crashes. what else could I possibly try? please help.

os: Windows 11 Home Firefox source: https://www.mozilla.org/en-US/firefox/all/desktop-release/win64/

p.s. this was posted through an android phone but the problem only occurs on windows

I am unable to open my profile on Firefox. I am using desktop and windows 11. I am typing this question on DuckDuckGo browser because I was unable to go in. It will not let me search, open new tabs, refuse to open new tabs and even to click on settings. I also tried to delete it in an attempt to log in again but it won't even let me delete it. The image I shared is all I see. No bookmarks, shortcuts, ways to do settings and other things. Thank you!

When I open Firefox in Windows 11 a small window appears that reads, "Firefox Couldn't load XPCOM. I have not found any solutions to stop this that work. Will Mozilla fix this?

Hi,

I am using OS MX-25 Linux and after importing my previous FF profile from an earlier version of MX everything in Firefox 145.0 was fine: my bookmarks and extensions all loaded and everything was tickety-boo. However, after I attempted to relaunch FF I got the following message:

Your Firefox profile cannot be loaded. It may be missing or inaccessible.

I have tried numerous times to launch FF but just keep getting this message.

Eventually it launched, but after a while pages refused to load properly and so I closed it down. Since then, I have been unable to get FF to open.

Any help would be greatly appreciated.

I downloaded firefox and it worked for about a month. Now when I try to launch it, the screen flashes momentarily as though it were about to pop up, but then it does not actually open a browser window. I have uninstalled and reinstalled firefox more than once, I've tried a simple restart of the computer, and tried multiple different update methods (updated windows). Any suggestions?

Tonight I received a notice that a new version of Firefox was available and asking if I wanted to download it. It showed me the new Kit mascot so I decided to let it install. It seemed to install normally but when it tried to open what I guess is a welcome/new features page, it crashes, and just showed a prompt to try again. This continued in an endless loop and I had to shut it down. Unfortunately I no longer had a functioning version available that I could find so I downoaded the ESR version to be safe (ver 140.5.0esr) which I am now using. Somehow I was able to recover bookmarks and hopefully other saved info. Can anyone advise what has happened? I have used Firefox for many years and never had this sort of problem before. Running Windows 11 on a new Dell i7 PC.

As per the topic title. I would like pages to always automatically translate from english to my chosen language. However, when I select the option in the context menu, then revisit the setting, the check box remains unchecked. This remains the case on multiple tested operating systems, Arch Linux and Linux Mint. Thank you in advance.

I originally deleted Firefox by accident and have downloaded it via Microsoft Store. All seems well then after I click on the app to open it, I Get the ‘Windows cannot find C:\Program Files\Mozilla Firefox\firefox.exe. Make sure you typed the name correctly, and try again’ for ‘Firefox’ error how can this be corrected?

I'm on Win10. This morning I see that MSLOP has updated my desktop PC overnight. FF was open before the update and attempted to restart but couldn't restore pages. I told it to start a new session and the PC blue screened. This has happened before so after the PC restarted I shut it down. It blue screened a few times while also trying to restart FF. I shut it down with the power button. FF will not start with troubleshooting (shift while double clicking on FF icon). It crashes and I get the crash window. Latest crash detail is below. What next? Any help is much appreciated.

UPDATE: I went to windows settings, apps, and clicked on uninstall for FF. Immediately a message box, "Would you like to refresh instead?" popped up. Sure, why not? It thought for a while and updated. I logged in again and I am back to a functioning 147.0.3. I logged into my bitwarden extension and ublock origin is still there. No clue what happened earlier.