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Firefox 28 OS X 10.7.5 hangs on startup in normal and safe mode, CPU 100%, reset does nothing

  • 7 replies
  • 3 have this problem
  • 2 views
  • Last reply by cor-el

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The application pegs the CPU usage to 100% within seconds of opening. The app must be force quit.

No window is opened and the menu bar only shows "Firefox". The cursor turns to a beach ball.

I tried opening in safe mode, then opening in safe mode with reset. No change. I then downloaded the app and opened a fresh version, same behavior.

The application pegs the CPU usage to 100% within seconds of opening. The app must be force quit. No window is opened and the menu bar only shows "Firefox". The cursor turns to a beach ball. I tried opening in safe mode, then opening in safe mode with reset. No change. I then downloaded the app and opened a fresh version, same behavior.

All Replies (7)

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Please try with a new profile, Profile Manager - Create, remove or switch Firefox profiles

Also, try to update to Mac 10.9.2, it is a free update for most Mac users of 10.6 and above.

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Firefox started with the new profile. I would like to know what caused the corruption of the default profile, though. Now that it works, I have get everything from my old profile into my new profile.

We are in a corporate environment, so updating our operating system is not going to happen.

Thanks.

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Clarify for me: You created a new profile for Firefox and you want to get your settings from your old to your new but without the corrupted data, correct?

Can you switch back to the old profile, then run about:support in the address bar, click Copy raw data to clipboard and then paste it in a new comment?

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The application doesn't get far enough to allow any input. It hangs before nearly immediately.

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If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over the problem

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I will be doing this. Thanks.

Still wish I knew what caused this and had a solution that would allow me to continue without having to spend hours recovering files.

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If the reset carried over the problem then it is possible that there is a problem with one of the involved SQLite database files (try places.sqlite).

When you reset Firefox then a new profile is created and some personal data (bookmarks, history, cookies, passwords, form data) is automatically imported and the current profile folder will be moved to the desktop to an "Old Firefox Data" folder.

Modified by cor-el