The problem was getting hold of the Logged in User Name and using that info to filter results of data held in a separate database.
After trying various suggestions, here is a simple solution that has worked for me ...
The following bit of script code which includes a Page_Load and the all important Session("name") = User.Identity.Name is placed on the page that has the asp:SqlDataSource.
When the page loads, the session variable is created ...
<%@ Page Title="" Language="VB" MasterPageFile="~/sitemaster.master" AutoEventWireup="false" CodeFile="My_Profile.aspx.vb" Inherits="Locums_My_Profile" %>
<script runat="server">
Sub Page_Load(ByVal Sender As Object, ByVal e As EventArgs) Handles Me.Load
Session("UserLogin") = User.Ide ...
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