What website is Firefox unable to connect to? Is the specific site listed in the address bar when you get that message?

If Firefox doesn't work with any site, please see this article for suggestions: Firefox can't load websites but other browsers can.

If you can get to another site by one of these methods, there might be a problem with your home/startup page:

• typing a URL in the address bar (for example, type mozilla.org in the address bar and press Enter)
• using a bookmark to a different site
• typing something in the search bar and pressing Enter to send it to your default search site
• using a desktop shortcut to a web page (if you have any)

Also, have you noticed any other unexpected changes in Firefox that might indicate a bad add-on or malware problem?

Thank you for the help. I was able to find the issue. I called AT&T and they said their website att.net has not been working the last couple of days and said to use start.att.net instead. Everything is good now, I can access my browser home page.