I'm sure this is pretty simple, but I'm missing something here.
I connect with our active directory without a problem using the following code (note - i found this online, it works. I have a book on AD Directory Services class, but at this point the code below works, without a full understanding of how it works. Until this project is complete, i'm on "make it work, learn how later" mode).
Dim authorizedUser As String = username
Dim phoneNum As String = ""
Dim entry As New DirectoryEntry(System.Configuration.ConfigurationManager.ConnectionStrings("ADConnectionString").ConnectionString)
Dim search As New DirectorySearcher(entry)
search.Filter = "(SAMAccountName=" & authorizedUser & ")"
search.PropertiesToLoad.Add("telephonenumber")
Dim result As SearchResult = search.FindOne()
...
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