it is going to ask for a username and password whether or not you use an IP address or hostname..
the easiest way to get around it is to "Map a network drive" in "My Computer" using some credentials that already exist on the computer that you are trying to access.
P.S. - If you install Teamviewer on your computers and PM me the login info, I will fix it for you. It's too much trouble trying to explain how to do it. This thread is already 3 pages long and we have like a dozen or more threads on this same topic.