I have a custom module where a user can create their own sub users to login and have limited access to their portal.  I have it working well, except I need to handle the case of duplicate userIDs for example the user 'andy' already exists so if a user tries to create a sub user also called 'andy' I get an error along the lines of Conflict in table "dbo.Users", column 'UserID'. The statement has been terminated.  Does DNN have a built in feature to catch this, if not I can build my own.

I am using Dim userCreateStatus As DotNetNuke.Security.Membership.UserCreateStatus = DotNetNuke.Security.Membership.UserCreateStatus.AddUser  Dim objNewUser As New UserInfo, and then passing a number of textboxes to the objNewUser, and finally userCreateStatus = UserController.CreateUser(objNewUser) then I return the UserID and send them an email and put them in the appropriate roll. 

It seems to work unless I put a username in that I know already exists, then I get the UserID conflict, but I do have an additional custom security table granting acces to different portions of the portal, so that may also be causing trouble.

does DNN have anything that automatically suggests an alternate login for a user so if I entered "andy" it might suggest "andy2" or other avaiable usernames?  I already wrote a custom if statement that checks the Users table and prompts the user to try again, but I would prefer to not frustrate my users by asking them to try again several times before they get an username that is not taken.

Thanks for the help.