Its sounds like Firefox is having a problem loading one of your Add-ons. Try restarting Firefox with the Add-ons disabled. You can find the "Restart with Add-ons Disabled" under the help menu. Here is a link to Firefox Safe Mode. http://support.mozilla.com/en-US/kb/Safe%20Mode If Firefox works in Safe Mode, turn-off all the Add-ons, re-start Firefox, then turn on the Add-ons one by one until Firefox crashes then go back and remove or disable that Add-on.