I played in the beta until it ended without any launcher issues. I tried to log in today after buying my copy and suddenly when I try and run the launcher it gives me the "The page cannot be displayed" cannot find server or DNS error page.
I thought something might have changed since the beta so I did a full uninstall/install and same issue.
the launcher uses MSHTML . If the IE browser is set to work offline or in the internet Options communications tab lan setting is set to use a proxy the launcher can not connect and you get the page not found error.
also if you have IE set to not display imgages it can also cause strange things to happen