Help! I'm setting up my home network and I have an external hdd connected to my brand new Airport Extreme, it's works great on my computer (Macbook Pro) but my roommates can't access the hdd because when they go to connect to it it says "Unknown User, reenter information, or talk to the network admin" I formatted it for smb so we could both use it, and it works if i plug it in directly to their computers, they run XP SP2. does anyone know how i can get around or fix this?? thanks.