I don’t think I’ve ever had a problem with a browser not launching before, but at some point last year I think I must have installed a dodgy browser extension then uninstalled it. From then on, Firefox just wouldn’t launch for me and I kept getting the Crash Reporter:
I tried all kinds of ways to resolve the issue. Having said that, I didn’t know about launching Firefox in Safe Mode (hold down the Shift key while launching Firefox) until just recently and that may have helped. If that doesn’t help, it does give you an option to restore Firefox to its factory default state while saving essential information. So this may be your best first option if Firefox doesn’t start for you.
Anyway, here’s my troubleshooting routine. I first ran malware scans with Malwarebytes Anti-Malware and SUPERAntiSpyware to see if that might be the problem but my system came up clean. I then tried uninstalling Firefox and reinstalling it. I tried uninstalling it using Revo Uninstaller and reinstalling. I tried launching Firefox from a portable version on a USB drive. I tried older versions of Firefox. None of these options worked and I just got the same old Crash Reporter error. I also tried restoring a Firefox profile I had backed up as discussed in my backup routine. That also didn’t work suggesting that both the profile and the backup profile may be corrupt and the cause of the problem.
So it seemed that as well as uninstalling Firefox I should also delete the browser profile. I tried that knowing that I would have to reinstall my Firefox extensions from scratch. This wasn’t a big deal as I’ve been using Chrome for 3 or 4 years now and I’m quite happy with it. But it’s nice to have a working backup browser just in case I ever experience any problems with Chrome. In Windows 7, the Firefox profile is at C:\Users\Username\AppData\Roaming\Mozilla\Firefox. So I uninstalled Firefox and deleted everything in this folder. I downloaded the latest Firefox installer and installed Firefox. During the installation, you do get the option to import your bookmarks, history, etc from Chrome, which is nice.
However, you have to reinstall your Firefox extensions again. Not really a problem in my case, just an opportunity to start again and install just what I actually need. And that was it, Firefox was working again. So the problem was a corrupt profile.
I hope that’s helped in troubleshooting Firefox when it won’t start. Lessons learned? Well I know about Firefox Safe Mode now, and I won’t backup a corrupt Firefox profile over a good one again.
Have you experienced any problems with Firefox not launching? How did you get it working again?