Hi, You can try to contact the company IT regarding the error message. In the meantime you could check if this happens in a [https://support.mozilla.org/en-US/kb/Managing-profiles new profile]. If the new profile is okay, you can then [https://support.mozilla.org/en-US/kb/reset-firefox-easily-fix-most-problems Reset Firefox] on the old (previous) profile via '''Help''' ('''Alt''' + '''H''') > '''Troubleshooting Information'''. If the error started after updating Firefox, you can try to install [https://addons.mozilla.org/en-US/firefox/addon/user-agent-switcher/ User Agent Switcher] and set it to the previous version of Firefox that worked. Please also see [http://chrispederick.com/work/user-agent-switcher/help/ this]. You can also try setting '''network.http.spdy.enabled''' to false in Firefox [http://kb.mozillazine.org/About:config about:config] [http://kb.mozillazine.org/About:config_entries about:config Entries]