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Windows 10. firefox will not load. I have uninstalled and reinstalled it. See it in task manager with a high CPU percent. Never loads.

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  • Last reply by FredMcD

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Windows 10. firefox will not load. I have uninstalled and reinstalled it. See it in task manager with a high CPU percent. Never loads.

Windows 10. firefox will not load. I have uninstalled and reinstalled it. See it in task manager with a high CPU percent. Never loads.

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Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

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


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}