Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Firefox crashes on start, even after complete reinstallation. No add-ons.

  • 3 replies
  • 3 have this problem
  • 13 views
  • Last reply by bob287

more options

Every time I open FF, it completely freezes within 5 seconds. I've uninstalled & reinstalled, I've removed FF & all traces of its data using Revo uninstaller, then reinstalled, and still get the same results. I've seen where malware could cause this kind of problem, so I've run full scans with Microsoft Security Essentials, Malwarebytes, Microsoft Security Scanner, and Kaspersky Security scanner. They all came back clean.

I'd love to submit a crash report, but apparently these crashes aren't generating them. The only thing in AppData\Roaming\Mozilla\Firefox\Crash Reports is an InstallTime file, dated today (the date of my most recent reinstall). I also can't add any troubleshooting information, as FF crashes before I can add anything.

Here's exactly what happens: I launch FF, whish responsive for the first couple seconds. After that, it freezes completely, and eventually "(Not Responding)" is added to the title bar. A little bit later, Windows pops up, asking if I'd like to check for a solution. That's it.

Win 7 Pro, FF 18.0.2.

Every time I open FF, it completely freezes within 5 seconds. I've uninstalled & reinstalled, I've removed FF & all traces of its data using Revo uninstaller, then reinstalled, and still get the same results. I've seen where malware could cause this kind of problem, so I've run full scans with Microsoft Security Essentials, Malwarebytes, Microsoft Security Scanner, and Kaspersky Security scanner. They all came back clean. I'd love to submit a crash report, but apparently these crashes aren't generating them. The only thing in AppData\Roaming\Mozilla\Firefox\Crash Reports is an InstallTime file, dated today (the date of my most recent reinstall). I also can't add any troubleshooting information, as FF crashes before I can add anything. Here's exactly what happens: I launch FF, whish responsive for the first couple seconds. After that, it freezes completely, and eventually "(Not Responding)" is added to the title bar. A little bit later, Windows pops up, asking if I'd like to check for a solution. That's it. Win 7 Pro, FF 18.0.2.

Chosen solution

The FF window wouldn't even appear when I tried to start it in safe mode (I had to kill the process), so I rebooted my computer into safe mode, and it worked. Looking at msconfig to find what might be causing the problem, I found a suspicious-looking entry that I was able to confirm was malware that all the scans missed. For reference, it was in AppData/Roaming/Elryu/onmo.exe. I'm sure those were randomly generated names, but I figure it's worth mentioning.

Everything's working perfectly now.

Thanks for your help - I mainly just didn't know where to start with my troubleshooting of FF, cause I'd never had problems with it before.

Read this answer in context 👍 1

All Replies (3)

more options

Hello bob287, can you start Firefox in Safe Mode by holding down the shift key while starting Firefox ?

also, try to boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps.


thank you

more options

If you can't open Firefox then see:


Try to boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps.

more options

Chosen Solution

The FF window wouldn't even appear when I tried to start it in safe mode (I had to kill the process), so I rebooted my computer into safe mode, and it worked. Looking at msconfig to find what might be causing the problem, I found a suspicious-looking entry that I was able to confirm was malware that all the scans missed. For reference, it was in AppData/Roaming/Elryu/onmo.exe. I'm sure those were randomly generated names, but I figure it's worth mentioning.

Everything's working perfectly now.

Thanks for your help - I mainly just didn't know where to start with my troubleshooting of FF, cause I'd never had problems with it before.