[RESOLVED] Why the Warning with my 'try catch finally end try' code?

[Megalith]

Why do i get a warning with my http? Trying to come to terms with try catch finally end try

        Dim myhttp As HttpWebRequest
        Dim html As String = ""
        Dim responseStream As Stream
        Dim WebResponse As HttpWebResponse
        Try
            myhttp = CType(WebRequest.Create(url), HttpWebRequest)
            WebResponse = CType(myhttp.GetResponse(), HttpWebResponse)
            responseStream = WebResponse.GetResponseStream()
            Dim reader As StreamReader = New StreamReader(responseStream, Encoding.Default)
            html = reader.ReadToEnd()

        Catch ex As HttpException
            MsgBox("Validation HTTP error" & vbCrLf & ex.Message)
        Catch ex As NullReferenceException
            MsgBox("Null value returned error")
        Catch ex As Exception
            MsgBox("Validation Other Exception error" & vbCrLf & ex.Message)
        Finally
            responseStream.Close()
        End Try

the code in the finally block to close the stream that may or may not have produced an error gives me a warning that the code may produce a null value, even with both an exception handler and with a null value handler.

I read about using nested try catch end try and wonder if i should try again if i get an error. Is it possible to say do the block if it errors give the user the option to try again or abort the app?

(afterthought this is sending an encrypted string to a server to validate before the app gives full access)