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Firefox won't start

  • 9 replies
  • 1 has this problem
  • 13 views
  • Last reply by FredMcD

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Firefox was working normally earlier in the day. I'm not aware of any updates on my computer. I didn't install add-ins. When I click the firefox icon to launch the program, the cursor momentarily has the hourglass symbol then nothing happens. There is not error message. Firefox is not shown in the task manager list. The firewall has mozilla firefox in the list of allowed programs. I've tried rebooting, reinstalling, the refresh tool, deleting appdata files, temp files, anything I could find in the registry with mozilla in the name, then rebooting again then reinstalling. I don't want to go back to Chrome... =(

Firefox was working normally earlier in the day. I'm not aware of any updates on my computer. I didn't install add-ins. When I click the firefox icon to launch the program, the cursor momentarily has the hourglass symbol then nothing happens. There is not error message. Firefox is not shown in the task manager list. The firewall has mozilla firefox in the list of allowed programs. I've tried rebooting, reinstalling, the refresh tool, deleting appdata files, temp files, anything I could find in the registry with mozilla in the name, then rebooting again then reinstalling. I don't want to go back to Chrome... =(

All Replies (9)

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hello, what kind of security software are you using on the affected system? can you get firefox to launch while you run windows in safe mode with networking enabled?

https://www.howtogeek.com/107511/how-to-boot-into-safe-mode-on-windows-8-the-easy-way/

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Thanks for the reply Philipp I started to restart in safe mode. I couldn’t do it because my system has bitlocker and I don’t have the recovery code on hand. I can try it when I get back to my office.

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Some problems occur when your Internet security program was set to trust the previous version of Firefox, but no longer recognizes your updated version as trusted. Now how to fix the problem: To allow Firefox to connect to the Internet again;

  • Make sure your Internet security software is up-to-date (i.e. you are running the latest version).
  • Remove Firefox from your program's list of trusted or recognized programs. For detailed instructions, see

Configure firewalls so that Firefox can access the Internet. {web link}

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Do you have Digital Guardian installed?

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Hi Jonathan. It’s a corporate machine. I believe we have cortex

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I restarted in safe mode. Firefox did not start in safe mode. Anymore ideas?

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What did you mean by that?

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The first response to the question is from Philipp. He suggested restarting windows in safe mode with networking because of the way some security software works.

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Start Firefox in Safe Mode {web link}

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?