Join the AMA (Ask Me Anything) with the Firefox leadership team to celebrate Firefox 20th anniversary and discuss Firefox’s future on Mozilla Connect. Mark your calendar on Thursday, November 14, 18:00 - 20:00 UTC!

This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

I just installed the most recent update. Now Firefox tries to start and then locks up.

  • 1 resposta
  • 3 have this problem
  • 1 view
  • Last reply by cor-el

more options

I just installed the most recent update. Firefox starts to load and then locks up. Cannot get homepage to load or go to any other websites.

User Agent

Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; GTB6.5; Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1) ; .NET CLR 1.1.4322; InfoPath.1; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.04506.648; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)

I just installed the most recent update. Firefox starts to load and then locks up. Cannot get homepage to load or go to any other websites. == User Agent == Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; GTB6.5; Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1) ; .NET CLR 1.1.4322; InfoPath.1; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.04506.648; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)

All Replies (1)

more options

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

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