Firefox doesn't have security zones like Internet Explorer. There's no Trusted Sites list to add sites to. Normally, web sites simply work, whether they're secure or not. If secure websites don't load, see the following article. * [[Websites don't load - troubleshoot and fix error messages]] If the website does load but you're having some other problem with it, see the following article. * [[Websites look wrong or appear differently than they should]] If neither of those answer your question, please post a link to the site and or a description of what doesn't work, or whatever error message is displayed.