Can not create another account on shared platform!?

Borrowed friend's computer to get started playing internet poker. First I registered on Party Poker. It was later suggested I play on Empire's site. I tried to register but wasn't allowed to. The site messaged me: cannot create another account on a shared poker platform. I thought I would just uninstall Party Poker then reregister on Empire; the same message occured. I then e-mailed Empire to get a response to my inability to register on their site. This is where I get totally confused: Empire responds by e-mail to my friend who lent me an extra computer on which he played poker, the same message I recieved--cannot create another account on a shared poker platform.
It seems to me Empire is confusing me with my friend but I don't know how. Please suggest a solution so that I can register on Empire.