Dim UrlTest As New System.Uri("http://www.google.com/")
' Setup WebRequest
Dim Risposta As System.Net.WebResponse
Dim Richiesta As System.Net.WebRequest
Richiesta = System.Net.WebRequest.Create(UrlTest)

Try
Risposta = Richiesta.GetResponse
Risposta.Close()
Richiesta = Nothing
Return True
Catch ex As Exception
Risposta.Close()
Richiesta = Nothing
Return False
End Try