Have you check your home page settings? This article has more information: https://support.mozilla.com/en-US/kb/how+to+set+the+home+page . Does that help?

"Clear the Cache": Tools > Options > Advanced > Network > Offline Storage (Cache): "Clear Now"<br /> "Remove the Cookies" from sites that cause problems: Tools > Options > Privacy > Cookies: "Show Cookies"<br /> <br /> Start Firefox in [[Safe Mode]] to check if one of your add-ons is causing your problem (switch to the DEFAULT theme: Tools > Add-ons > Themes).<br /> See [[Troubleshooting extensions and themes]] and [[Troubleshooting plugins]] ---- *http://kb.mozillazine.org/Websites_look_wrong *http://kb.mozillazine.org/Error_loading_websites (Error_loading_some_websites)