Wikipedia:Request an account/ACC Wizard/BadUsername

Wikipedia Request An Account Wizard
Username problems
Are you unable to create your account because of the username you've chosen?

The ACC process will be unable to help in nearly all of these cases. ACC tool users cannot bypass or override username issues in order to create the account for you. There are a few very limited exceptions in which the account creation process can assist with (see details below). Otherwise, you must choose a different username.

Common fixes and solutions to errors regarding your chosen username:
My username is already taken
If the username is already taken by another Wikipedia or Wikimedia account, you must choose a different username. The other account's contributions, age, activity or inactivity status, block or ban status, or global lock status is irrelevant - the username will always be considered to be unavailable. Before proceeding to use the ACC process to request the creation of an account, you need to check if the username you'd like to use is already taken. You can do this by clicking here and entering the username (case sensitive) into the field. If the page doesn't return an error stating that "there is no global account for '[your chosen username]'", the username is already taken and unavailable, and you must choose a different username.
My username is invalid
Usernames containing #, <, >, [, ], |, {, }, _, /, @, or : are invalid and cannot be created. You must choose a different username. It's also important to note that there are additional characters that, while allowed in usernames, will cause other issues, restrictions, and errors with your account until the username is changed and no longer contains them. More details about this are available by clicking here.
My username has been blacklisted
Certain words, phrases, and characters are not permitted in usernames because they violate the username policy. In this situation, you must choose a different one. However, if the username you'd like to use is triggering the blacklist, and if you believe that your chosen username does not violate the username policy, you may request that it be created for you.
My username is too similar to another username
If the username you chose is determined by the MediaWiki software to be similar to the username of another editor, the software will automatically prevent you from creating the account. The software will also prevent creation of usernames that match the previous usernames of accounts that have been renamed. In most cases, you must choose a different one.
If the similar account is inactive, has not been used in a very long time, and has made very few edits, the account creation team can override the automatic filter to create your account. See this section of the account creation request processing guide for more information regarding how this is determined.