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Firefox won't start, also unable to activate safe mode

  • 3 replies
  • 2 have this problem
  • 1 view
  • Last reply by FredMcD

RayAP9
RayAP9
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Firefox was working fine until I restarted my PC today (which runs Windows 7 Ultimate), and now it won't open no matter how many times I click the taskbar icon or the Start Menu/desktop shortcut.

One popular fix I noticed while troubleshooting is to reset Firefox by holding shift while opening the program, then selecting the "reset" option. Holding shift while I try to open it does nothing.

I tried restarting my PC multiple times, and tried starting it up in Safe Mode with Networking. I've also uninstalled and reinstalled Firefox twice. Same problem.

Any suggestions? Thank you.

Firefox was working fine until I restarted my PC today (which runs Windows 7 Ultimate), and now it won't open no matter how many times I click the taskbar icon or the Start Menu/desktop shortcut. One popular fix I noticed while troubleshooting is to reset Firefox by holding shift while opening the program, then selecting the "reset" option. Holding shift while I try to open it does nothing. I tried restarting my PC multiple times, and tried starting it up in Safe Mode with Networking. I've also uninstalled and reinstalled Firefox twice. Same problem. Any suggestions? Thank you.

All Replies (3)

FredMcD
FredMcD
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Start your Computer in safe mode with networking. Then start Firefox. Try Safe web sites. Is the problem still there?

Starting The Computer In Safe Mode;
Free Online Encyclopedia

RayAP9
RayAP9 Question owner
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FredMcD said

Start your Computer in safe mode with networking. Then start Firefox. Try Safe web sites. Is the problem still there? Starting The Computer In Safe Mode;
Free Online Encyclopedia

Yes, when I started my PC in Safe Mode with Networking, the same problem occurred.

Running the Windows troubleshooter tells me that Firefox is an "incompatible application."

Modified by RayAP9

FredMcD
FredMcD
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Shut down Firefox. Using your file browser, open the Programs Folder on your computer.

Windows: C:\Program Files C:\Program Files (x86)

Right click on Firefox.exe and select Properties. Now select Compatibility. Turn Off Run This Program In Compatibility Mode, and Run This Program As An Administrator.

Do the same for any Firefox shortcuts you have. Now restart Firefox.