Here is what the e-mail said:
The SW Combine Administration has declined your membership application providing the following reason :
Your handle does not match out current rules requirements. It was turned down because of the presence of a restricted name or adjective, such as 'Lord', 'Count' or 'Darth', or an existing Star Wars character name was chosen such as 'Luke Skywalker' or 'Han Solo'. Please refer to the Character Creation rules page located at http://rules.swcombine.com/character/charactercreation/ for more information.
Please make the necessary changes and try again. If you have any questions or queries feel free to post on the post on the Problem Centre
or visit the help room on IRC, #swc-help.