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Firefox crashes and won't start after upgrade to 9.01

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  • 43 have this problem
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  • Last reply by cor-el

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Firefox will not start at all after upgrade to 9.01.

Firefox will not start at all after upgrade to 9.01.

All Replies (5)

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Try following the instructions here: Firefox will not start

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That can be a problem with the Norton toolbar (coFFPlgn.dll).

See Firefox 9 Support for Norton Toolbar:

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I am using McAfee Total Protection instead of Norton But the same issue. I can not start Firefox past version 9.

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First of all you could try installing the latest version and see if that would fix the problem

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Does Firefox crash (you get a Firefox has crash window) or does Firefox simply doesn't start?

See:


A possible cause is security software (firewall,anti-virus) that blocks or restricts Firefox or the plugin-container process without informing you, possibly after detecting changes (update) to the Firefox program.

Remove all rules for Firefox and the plugin-container from the permissions list in the firewall and let your firewall ask again for permission to get full unrestricted access to internet for Firefox and the plugin-container process and the updater process.

See: