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firefox does not startup it is at 100% cpu after upgrade

  • 3 replies
  • 1 has this problem
  • 2 views
  • Last reply by StarCity

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Upgrade to 9.0.1 went smoothly from an old firefox, but when it tried to startup firefox browser after the upgrade, the browser window came-up, but unable to click or do anything in the window and the firefox process is running about 99% of CPU. Let it run until it consumed 30 minutes of CPU. Also, installing in a new directory did not help, but had not uninstalled the other copy.

Running on an old XP machine which just recently upgraded to SP2 and recently installed AVG, but even temporarily turning off anti virus software did not seem to help. Able to use an old IE, though on occassion also see performance issue (but suspect anti virus?).

I could uninstall the old Firefox, but I do not want to loose bookmarks, etc. as I can not export them because I can not bring-up the browser.

Upgrade to 9.0.1 went smoothly from an old firefox, but when it tried to startup firefox browser after the upgrade, the browser window came-up, but unable to click or do anything in the window and the firefox process is running about 99% of CPU. Let it run until it consumed 30 minutes of CPU. Also, installing in a new directory did not help, but had not uninstalled the other copy. Running on an old XP machine which just recently upgraded to SP2 and recently installed AVG, but even temporarily turning off anti virus software did not seem to help. Able to use an old IE, though on occassion also see performance issue (but suspect anti virus?). I could uninstall the old Firefox, but I do not want to loose bookmarks, etc. as I can not export them because I can not bring-up the browser.

All Replies (3)

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Hi StarCity,

Have you looked at the Knowledge Base article Firefox uses too much memory or CPU resources - How to fix or Firefox uses too much memory or CPU resources - How to fix? There is a lot of great information in there.

Hopefully this helps!

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Thanks for pointing those links, but that did not resolve my issue. I tried bringing it up in safe mode, but it still was at 100% and not responding. Regarding the other suggestions, I am running the most current version(that is when problem started), and since it comes-up in a non-responding manner, most of those other suggestions do not apply. Any suggestions?

Should I attempt uninstalling? If so, will saving my default profile directory be sufficient to be able to restore my bookmarks in the future?

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Problem resolved. Solution was to create a new profile, will alter check into importing old bookmarks, etc. The standard debugging steps in http://kb.mozillazine.org/Standard_diagnostic_-_Firefox led to the resolution of the problem.