There is a much easier way to accomplish this:

vb.net Code:
  1. Dim GetRemoteValue As New WebClient()
  2. Dim remoteValue As String = GetRemoteValue.DownloadString("http://yoururl.com/version.txt")
  3. GetRemoteValue.Dispose()
  4.  
  5. If remoteValue > Application.ProductVersion Then
  6.     'do youre thing
  7. End if