Firefox Community Forum

Through extensive troubleshooting, I am unable to get firefox to open at all.

I've done a full uninstall, cleaned all user directories, program files / x86, program data, appdata roaming and local, etc. I used the Microsoft uninstaller and even Revo Uninstaller to remove everything related to Firefox, did a restart and reinstall of the latest one and it still won't launch.

Firefox was previously working until a reboot occurred and now it won't launch.

Firefox 32 bit seems to work when installed, and running Firefox as an admin previously worked but no it no longer does.

I looked at the following articles: - https://support.mozilla.org/en-US/kb/firefox-wont-start-find-solutions - https://support.mozilla.org/en-US/kb/profile-manager-create-remove-switch-firefox-profiles - https://support.mozilla.org/en-US/kb/profile-manager-create-remove-switch-firefox-profiles#w_start-the-profile-manager-when-firefox-is-closed

There's no malware on this machine (business EDR on it, even disabled it as a test and it still didn't open).

I was able to launch the profile manager but now I am unable to as the processes launch in task manager and then within 5 seconds they close.

Firefox is not running in the background for any user (I'm the only one logged in after a reboot as well)

I'm unable to open in troubleshoot mode either. Tried run as and admin cmd "C:\Program Files\Mozilla Firefox\firefox.exe" -safe-mode

Ran SFC / scannow / DISM restore health commands as well and both came back fine / no integrity violations

Actually this is just the only route I could figure out to your page where I had PREVIOUSLY asked this question and was checking back in to see whether 'the Community' had given me an answer yet. I'm no doubt IMPATIENT since my bank told me I need you, not Google and Microsoft Edge , who I both HATE for coming on to MY laptop, asking for more information sharing and basically DEMANDING I follow their marketing instructions since they had somehow REMOVED the X at the top right corner and simultaneously BLOCKED my access to and use of my OWN laptop, so that each time I have NO OPTION but to turn off the power on my laptop, to "reboot" as they once said. If even a basic, ancient telephone can be HUNG UP on scammers.....forgive me. I REALLY want to use your search engine, as WELL as your site. Please advise.

Firefox 146.0.1 crashes every time upon launch (basically fails to launch), even in troubleshooting mode, with exception code 0xc0000005. Prior to today, it was working fine. Windows does not show any updates made over the last couple of days. I am on Windows 11 25H2, and I'm current with updates. Chrome works. Edge works. I logged on to the same computer as a different user (different profile folder in the user AppData folder) and Firefox still does not work. I tried to refresh Firefox and that did not resolve the issue. I tried to uninstall and reinstall Firefox and that did not resolve the issue. I tried to run DISM and SCANNOW and that did not resolve the issue. No issues are detected with a virus scan. I am stumped - please help!

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!

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.

Mozilla Firefox is very slow and even difficult to open.....I am using this browser since ten years and never had any problem....Please do the needful at your earliest...Thank a lot....RASIK MER

Mozilla Firefox is very slow and even difficult to open.....I am using this browser since ten years and never had any problem....Please do the needful at your earliest...Thank a lot....RASIK MER

Please tell me how to resolve this issue. The 3 reports I have submitted from the crash window are:

Crash ID: ⁨bp-4107d3db-4280-445b-a0cd-e96400251020⁩ [10/20/2025 2:43 PM (Pacific)] Crash ID: ⁨bp-b5e0bbf3-d4f6-4b2a-898a-f56960251020⁩ [10/20/2025 2:40 PM (Pacific)] Crash ID: ⁨bp-975fcb26-5886-492f-8253-e37820251020⁩ [10/20/2025 2:39 PM (Pacific)]

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.

As title: after running updates, Firefox consistently crashes when launching.

To give more concrete details:

-Running on Linux, specifically KDE Fedora 42. Firefox was updated to 142 from 141, alongside various other updates. -When launching Firefox from any source (directly, through a link, through the terminal etc.), the only window that appears is the crash reporter. -This issue occurs when launching in safe mode. Removing and reinstalling Firefox, including deleting the entire .mozilla folder in Home at the same time does not resolve the issue. I am unable to test rolling Firefox back to 141. -When attempting to launch from the terminal (safe mode or otherwise), the following is output (personal info redacted):

restorecon: SELinux: Could not get canonical path for /home/[username]/.mozilla/firefox/*/gmp-widevinecdm/* restorecon: No such file or directory.

/usr/include/c++/15/array:210: constexpr std::array<_Tp, _Nm>::value_type& std::array<_Tp, _Nm>::operator[](size_type) [with _Tp = HeaderBarButtonType; long unsigned int _Nm = 3; reference = HeaderBarButtonType&; size_type = long unsigned int]: Assertion '__n < this->size()' failed.

Redirecting call to abort() to mozalloc_abort

[ExceptionHandler generates a minidump etc.]

Gtk-Message: [timestamp]: Failed to load module "appmenu-gtk-module"

(I would note that to the best of my knowledge I had not included a plugin for decoding widevine in my Firefox setup, and certainly the Firefox 141 instance on the device being used to write this post (same OS) does not include it) -The crash files in the .mozilla folder, meanwhile, consistently list a segfault at address 0x0.

Any advice on diagnosing/solving this issue would be greatly appreciated. Let me know if there's any other information that would be helpful.

If it would be more appropriate, I could report this through Mozilla's bugzilla instance, but given the issue seems to be very niche (Fedora's ABRT shows a total of 5 unique affected users in the last few days) I am unsure whether flagging this there would be appropriate.

Hi, my Machine updated from 140.0.4 to 141.0 since then I cannot start up Firefox anymore. On startup after a short pause the Crash Reporter shows up - interestingly the Crash Reporter may enter a endless loop and opens up multiple times. While that the CPU load is at 100%. I tried

• `firefox --safe-mode`
• `firefox --ProfileManager`

as well, for those I get the same behavior. I tried downgrading to 140.0.4 - after that a profile dialog shows up which tells me that a new profile needs to be created due to a downgrade. After that Firefox comes up fine with the new vanilla profile. IF Firefox updates to 141.0 (in background) the next startup with the vanilla profile doesn't work gain. Which brings me back to the initial problem.

Workaround for now:

• download 140.0.4
• create a fresh profile
• immediately disable auto update
• live with the empty profile

My environment:

• Linux Debian 12 on x86_64
• KDE Plasma
• nvidia drivers installed
• I am using Firefox from `https://download-installer.cdn.mozilla.net/pub/firefox/releases`

When I try to open Firefox it opens hundreds of crash reporter dialogue boxes and makes my computer slow to a halt, only restarting my computer can stop the onslaught. Resolving a dialogue/close all doesn't help.

I've tried holding shift to start in troubleshoot mode, but it just opens the crash boxes rather than the 'do you want to start in troubleshoot' box.

I've run a scan with Malwarebytes, no hits, and Windows says there's no updates for me. I can't see any specific crash number, the 'submit' file in my Crash Reports folder says this:

[WARN crashreporter::net::ping] not sending legacy crash ping because no ping directory configured [WARN crashreporter::logic] not updating the events file; no events directory configured [ERROR crashreporter::net::http] background task error: process failed (exit status exit code: 1073807364) with [ERROR crashreporter::net::http] background task error: process failed (exit status exit code: 1073807364) with stderr: stderr: er::glean::uploader] failed to send glean ping: process fail[ERROR crashreporter::glean::[ERROR crashreporter::net::http] background task error: process failed (exit status exit code: 1073807364) with stderr: upload] Recoverable upload failure while attempting to send ping 9746c2ff-0e8b-47b5-bc82-3a14fbf8a[ERROR crashreporter::net::http] background task error: process failed (exit status exit code: 1073807364) with stderr:

-- 0

[WARN glean_core::upload] Recoverable upload failure while attempting to send ping 7be8924c-9a93-4169-8ff3-c29b26b5f75c, will retry. Error was RecoverableFailure { unused: 0 } [WARN glean_core::upload::directory] Cannot find ping file to process 7be8924c-9a93-4169-8ff3-c29b26b5f75c

                                                                                                                                                                                                                                                         [ERROR crashreporter::net::http] background task error: process failed (exit status exit code: 0xc000026b) with stderr:

And here is what I get when I click 'details' on the crash reporter:

BuildID: 20250717180000 CrashTime: 1753234799 InstallTime: 1753232273 ModuleSignatureInfo: {"Microsoft Windows":["bcryptPrimitives.dll","wininet.dll","urlmon.dll","srvcli.dll","iertutil.dll","ktmw32.dll","version.dll","wsock32.dll","propsys.dll","uxtheme.dll","kernel.appcore.dll","windows.storage.dll","ntmarta.dll","netutils.dll","CRYPTBASE.dll","wldp.dll","ntasn1.dll","ncrypt.dll","msasn1.dll","sspicli.dll","profapi.dll","wintrust.dll","ucrtbase.dll","gdi32full.dll","bcrypt.dll","KERNELBASE.dll","crypt32.dll","msvcp_win.dll","win32u.dll","sechost.dll","imagehlp.dll","gdi32.dll","shlwapi.dll","ws2_32.dll","oleaut32.dll","SHCore.dll","advapi32.dll","psapi.dll","imm32.dll","msvcrt.dll","shell32.dll","kernel32.dll","combase.dll","ole32.dll","user32.dll","rpcrt4.dll","ntdll.dll","kbdus.dll"],"Mozilla Corporation":["firefox.exe","gkcodecs.dll","nss3.dll","mozglue.dll","lgpllibs.dll"],"Malwarebytes Inc":["mbae64.dll"],"Microsoft Windows Software Compatibility Publisher":["msvcp140.dll","VCRUNTIME140.dll","VCRUNTIME140_1.dll"]} ProductID: {ec8030f7-c20a-464f-9b0e-13a3a9e97384} ProductName: Firefox ReleaseChannel: release StartupTime: 1753234797 SubmittedFrom: Client Throttleable: 1 UptimeTS: 2.0 Vendor: Mozilla Version: 141.0 WindowsErrorReporting: 1 This report also contains technical information about the state of the application when it crashed.ii

I launch Firefox from a shortcut in the QuickLaunch bar. I need to double-click that to get a response. But then TWO instances of Firefox open, and I have to close one - which seems a waste of time and effort over and over and over. My system is x32Win10ProV22H2. How to get just one instance ?

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