Try manually typing in
http://www. before the address? (Random technobabble on the topic
here. Basically at some point, "www" stop being necessary for
most websites so whether or not the browser automatically assumes you need it depends on the browser and, well, the site itself. People are smart enough to link their sites properly and browsers are smart enough to follow paths correctly, but if you're manually typing site urls in... yeah, some of them do require "www" and browsers no longer automatically supply that behind the fold. It's kind of a security thing? I dunno. )