I would first of all attempt to log in from a different IP. If, for some reason, the password/user was incorrect, your current IP may be blocked. I would also confirm the the FQDN is "translating" to the correct public IP.There are a number of sites that will do that for you, if you do a search. You could also use tracert in a command prompt window, if using Windows, the first line returned will show the public IP.