One of your add-ons might be the culprit. Try running Firefox in Diagnose Firefox issues using Troubleshoot Mode. If that solves the problem, see Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems and possibly Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems

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If that does not solve the problem, a new profile Then, Recover your data from the old profile. See http://support.mozilla.com/en-US/kb/Recovering+important+data+from+an+old+profile

The safe mode didn't work and nethier did the other the browser window will not open. any other ideas? thanks

See http://kb.mozillazine.org/Browser_will_not_start_up

A possible cause is security software (firewall) that blocks or restricts Firefox without informing you about that, possibly after detecting changes (update) to the Firefox program.

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

See Server Not Found - Troubleshoot connection problems and Configure firewalls so that Firefox can access the Internet and http://kb.mozillazine.org/Firewalls