I'm in it all day everyday with no issues. see screenshot outlook.live.com Have you tried Firefox in Safe Mode? https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode#search Did you clear your browser cache? https://support.mozilla.org/en-US/kb/clear-cookies-and-site-data-firefox

You can check the connection settings. *Settings -> General -> Network: Connection -> Settings If you do not need to use a proxy to connect to internet then try to select "No Proxy" if "Use the system proxy settings" or one of the others do not work properly. See "Firefox connection settings": *https://support.mozilla.org/en-US/kb/websites-dont-load-troubleshoot-and-fix-errors *https://support.mozilla.org/en-US/kb/firefox-cant-load-websites-other-browsers-can *https://support.mozilla.org/en-US/kb/firefox-and-other-browsers-cant-load-websites