i am trying to implement asp.net membership, profile and role based security in a windows application by configuring client Application Services for my windows forms application. I have followed both these articles http://www.dotnetbips.com/articles/e863aa3c-0dd6-468d-bd35-120a334c5030.aspx and http://msdn.microsoft.com/en-us/library/bb546195.aspx step-by-step but for some reason i can't get the authentication working.

I have a deployed intranet asp.net website which is already using an asp.net membership database for authentication and want to use that same database for authenitcation in my windows forms application. The site URL is http://myServer_Name:My_Port and i am specifying that URL as the both the Authentication service location and Roles service location in the windows application services property tab.

But in the windows application login form, when i say

   Dim msg As String = "Welcome "
    If Not Membership.ValidateUser(UsernameTextBox.Text), PasswordTextBox.Text)) Then
        MessageBox.Show("Invalid User ID or Password!")
    Else
        msg = msg + UsernameTextBox.Text
    End If 

i get my "Invalid User ID or Password!" message even when i supply a valid user name with the corresponding password. i am able to login with the same credentials from the asp.net site.

How can i test if the Authentication service location is being reached from the windows application??

Or what other information can i provide here such that one is able to help me get this working??