Trying to get Roles to populate a checkboxlist based on tutorial and having issues.

I have been using the following tutorial and had to convert the code to C# for my project, now i cant get the code to work, im getting red line under the word "in" in the UpdateRolesFromList,
i tried to add a datasource on page load for the checkboxlist like so RoleList.DataSource = PopulateRoleList(User.Identity.Name.ToString());
and gives me error saying cannot implictly convert type 'void' to 'object'
http://weblogs.asp.net/scottgu/pages/Recipe_3A00_-Implementing-Role_2D00_Based-Security-with-ASP.NET-2.0-using-Windows-Authentication-and-SQL-Server.aspx
What am i missing, that when i load the page or even do a search it never displays the checkbox list as it shows in the tutorial?
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