I think that ProBoard is basically a hosted version of YaBB 1. If you have access to an FTP, you can try Invision, phpBB or YaBB, but otherwise you'll have to use a crappy board hosting service which places ads on your forum.
Also, you shouldn't create a board and expect people to go to it unless you have enough people to start a community there, as well as a good reason for others to join. Otherwise nobody will bother.
Unfortunately, I think you'll fall under the category titled "Worthless boards with only a few registered users and no activity".