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Unable to open Firefox.


I've used Firefox for a long time but today it would not open and acess internet. I deleted the program, restarted computer and reload Firefox4. Restarted again and the same thing happened; it will not open. What happened and how do I fix?

Additional System Details

This happened

Every time Firefox opened

This started when...



  • User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; MDDC; .NET4.0C)

More Information

  • Moderator
1041 solutions 8840 answers

Try this troubleshooting guide - https://support.mozilla.com/kb/Firefox+will+not+start