MediaWiki:Titleblacklist-forbidden-new-account

You can not use "$2" As your username.

Please use a real name for the user name, or at least one with two capitalized words separated by a space.

User names need to be comprised of two names separated by a space. Each name must be capitalized.

E.g.: Apologies for the inconvenience, we're fighting heavy spam and vandalism. (If you really don't want to use your real name, you could use something like "Jim Motorbike")
 * "Mary Smith". OK.
 * "MarySmith". Invalid.
 * "Mary smith". Invalid.
 * "marysmith". Invalid.