ASP.NET sees the session cookie and loads the session (or doesn't, and starts a new one). This is why people recommend serving static, unauthenticated resources like images from a separate domain.

Help! This is really strange, as it seems correct to me. Code: Dim PKID As Guid = Membership.GetUser(User.Identity.Name).ProviderUserKey sqlCmd.Parameters.AddWithValue("@PKID", PKID) ...