You already provided the crash ID which is great, but beyond my expertise. I am sure you will get feedback on that.

You mention you have not made any significant changes lately. Any automatic Windows update by any chance?

What you could do is Reset Firefox. The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information. Note: This will cause you to lose any Extensions, Open websites, and some Preferences.

To Reset Firefox do the following:

1. Go to Firefox > Help > Troubleshooting Information.
2. Click the "Reset Firefox" button.
3. Firefox will close and reset. After Firefox is done, it will show a window with the information that is imported. Click Finish.
4. Firefox will open with all factory defaults applied.

Further information can be found in the Refresh Firefox - reset add-ons and settings article.

First of all, thank you for responding!

Windows update hasn't run recently, no. I honestly don't know what could have changed since I last used Firefox successfully. It was working just fine, then I closed it, then later I came back (maybe an hour or two afterwards) and tried to fire it up again. That's when the crashing started, seemingly out of nowhere.

Also, I REALLY don't want to have to reset Firefox. It would be an extreme pain in the backside to get it set back up the way I had it afterwards. I have several extensions that I refuse to browse without, each with their options set up just the way I like them.

Just a quick update: I tried a few other things, including trying to start with a new profile by going to Start>Run and entering "firefox.exe -p", with no results. I also tried the run command to start safe mode, and have the same problem.

Also, I REALLY don't want to have to reset Firefox. It would be an extreme pain in the backside to get it set back up the way I had it afterwards.

I know how it feels... Still, the way you have it now, is not something you can live with. Have you tried Safe mode? Safe Mode is a troubleshooting mode, which disables for the time being (!) most add-ons.

(If you're not using it, switch to the Default theme.)

• You can open Firefox 4.0+ in Safe Mode by holding the Shift key when you open the Firefox desktop or Start menu shortcut.
• Or open the Help menu and click on the Restart with Add-ons Disabled... menu item while Firefox is running.

Once you get the pop-up, just select "'Start in Safe Mode"

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension, and you need to figure out which one. Please follow the Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems article for that.

To exit the Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.

When you figure out what's causing your issues, please let us know. It might help other users who have the same problem.

Do a clean reinstall and delete the Firefox program folder before (re)installing a fresh copy of the current Firefox release.

Download a fresh Firefox copy and save the file to the desktop.

• Firefox 20.0.x: http://www.mozilla.org/en-US/firefox/all.html

Uninstall your current Firefox version, if possible, to cleanup the Windows registry and settings in security software.

• Do NOT remove personal data when you uninstall your current Firefox version, because all profile folders will be removed and you will lose all personal data like bookmarks and passwords from profiles of other Firefox versions.

Remove the Firefox program folder before installing that newly downloaded copy of the Firefox installer.

• (32 bit Windows) "C:\Program Files\Mozilla Firefox\"
• (64 bit Windows) "C:\Program Files (x86)\Mozilla Firefox\"

• It is important to delete the Firefox program folder to remove all the files and make sure that there are no problems with files that were leftover after uninstalling.
• http://kb.mozillazine.org/Uninstalling_Firefox

Your bookmarks and other personal data are stored in the Firefox profile folder and won't be affected by an uninstall and (re)install, but make sure that "remove personal data" is NOT selected when you uninstall Firefox.

If you keep having problems then also create a new profile.

• http://kb.mozillazine.org/Profile_folder_-_Firefox
• http://kb.mozillazine.org/Profile_backup

• http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Clean_reinstall