Wont let me log in a second accnt

[Magicstan]

Ok, I try making a 2nd accnt and it gives me the message "we were unable to authenticate your login usually this mean....etc etc etc" i was curious if this would work with one of my buddies accnts...and sure enough My computer wont let me log in his account either. Whats going on?

[Levey the miner]

i am also having this problem trying to make a account for my buddy