When you register a username an e-mail is sent out to the e-mail address you registered. Contained in that e-mail are instructions on how to activate your account. If you don't follow the directions in the e-mail then the account won't be activated. But depending on how reliable your e-mail service is the e-mail might have gotten lost. If that's the case you obviously didn't get the instructions

hehe.
I went ahead and registered the account for her so she doesn't have to do it anymore. If she's still having problems feel free to post again or e-mail/PM me and I'll be happy to help.
Thanks.