function not returning true value

I have a call to a function in my business logic area.  It should be returning a true. 
http://www.katebransfield.com/r_link-partners-real-estate-homes.asp
This url above is the culprit. The code doesn't seem to like the .asp type of file.  I wonder why this is the case.  I get a true response for a html or php type of file.  The above returns false. Does anyone know why?
 
If SiteFuncs.IsValidUrl(advLnk.ReciprocalURL) = False Then Me.lblMsg.Text = "The reciprocal url is invalid" Exit Sub End If  
Public Shared Function IsValidUrl(ByVal url As String) As Boolean 'this only works on the remote servers. url = MakeURL(url) Try Dim request As WebReq ...