I finally succeeded in completing registration on this site. I first attempted to do this a week ago using one e-mail address, and a handle with a subscript (_) in it. I didn't have an e-mail 3 days later and thought because I unchecked "receive e-mail from administrators" option that a bug occurred skipping on the registration e-mail. I then tried to register with another alias that contained a _, using a different e-mail and left the e-mail from administrators option checked. This did not work either. I then made a yahoo mail account and registered a name without any subscripts and succeeded. I checked my spam folders on the first 2 e-mail addresses and never found a physics forum e-mail. I think your software may have issue with either the mail system or the handling of names that contain subscripts.