You must call the "WebSecurity.InitializeDatabaseConnection" method before you call any other method of the "WebSecurity" class
In the Account Controller Register action (public ActionResult Register(RegisterModel model)) I have a code below that by default assign a Customer Role to a new user during registration. In my database, the defined roles are "Administrator" and "Customer". However, the code below generates exception as stated on the title post. SimpleRoleProvider role = new SimpleRoleProvider(); role.AddUsersToRoles( new string [] { model.UserName }, new string [] { "Customer" }); The solution would be to use the Role class defined in System.Web.Security namespace instead of SimpleRoleProvider: Roles.AddUserToRole(model.UserName, "Customer" ); Reference: Perils of MVC 4 AccountController Cheers! :)