This file is either not under source control or this user name is not recognized.

You're trying to use the Add to Source Control command to put a file under source control. However, either source control is not installed on the Web server, or the server doesn't recognize your user name.

• To correct this error, set up source control on your server.

  -or-

  Establish yourself as a user on the server.

For more information, see Source Control and Security.