I have a routine I call to post XML from vb.net to a url over http

It can be the XML file can be quite a size sometime I expect it to
exceed 10mb.
I started using a routine to post the file to a URL from vb.net, but
didnt realise there would be a restiction on post size.
So from this function :

        Dim result As String = ""
        Dim mywriter As IO.StreamWriter
        Dim strXML = xmlDoc.InnerXml()
        Dim bojRequest As System.Net.HttpWebRequest =
System.Net.HttpWebRequest.Create(postUrl)

        bojRequest.Method = "POST"
        bojRequest.ContentLength = strXML.Length
        bojRequest.ContentType = "text/xml"

        Dim myCred As New System.Net.NetworkCredential(postUsername,
postPassword)
        bojRequest.Credentials = myCred

        Try
            mywriter = New
IO.StreamWriter(bojRequest.GetRequestStream())
            mywriter.Write(strXML)
            mywriter.Flush()
            mywriter.Close()
            mywriter = Nothing

            Dim objResponse As System.Net.HttpWebResponse =
bojRequest.GetResponse()
            Dim sr As IO.StreamReader
            sr = New IO.StreamReader(objResponse.GetResponseStream())
            result = sr.ReadToEnd
            sr.Close()
            sr = Nothing
        Catch ex As Exception
            Return ex.Message
        End Try

I got this return:
Bytes to be written to the stream exceed the Content-Length bytes size
specified, but the function works when sizes are good.
Im not sure how to fix this so I googled areound and came up with this:

        Try
            Dim req As WebRequest
            Dim RequestStream As Stream
            Dim ReceiveStream As Stream
            Dim encode As Encoding
            Dim sr As StreamReader
            Dim payload As String
            req = WebRequest.Create(postUrl)
            req.Method = "POST"
            req.ContentType = "text/xml"
            Dim SomeBytes() As Byte
            Dim UrlEncoded As New StringBuilder
            Dim reserved() As Char = {ChrW(63), ChrW(61), ChrW(38)}
            Dim result As WebResponse

            payload = xmlDoc.InnerXml
            If payload <> Nothing Then
                Dim i As Integer = 0
                Dim j As Integer
                While i < payload.Length
                    j = payload.IndexOfAny(reserved, i)
                    If j = -1 Then

UrlEncoded.Append(HttpUtility.UrlEncode(payload.Substring(i,
payload.Length - i)))

'UrlEncoded.Append(URLEncode(payload.Substring(i, payload.Length - i)))
                        Exit While
                    End If

UrlEncoded.Append(HttpUtility.UrlEncode(payload.Substring(i, j - i)))
                    UrlEncoded.Append(payload.Substring(j, 1))
                    i = j + 1
                End While
                SomeBytes =
System.Text.Encoding.UTF8.GetBytes(UrlEncoded.ToString())
                req.ContentLength = SomeBytes.Length
                RequestStream = req.GetRequestStream()
                RequestStream.Write(SomeBytes, 0, SomeBytes.Length)
                RequestStream.Close()
            Else
                req.ContentLength = 0
            End If
            result = req.GetResponse()
            ReceiveStream = result.GetResponseStream()
            encode = System.Text.Encoding.GetEncoding("utf-8")
            sr = New StreamReader(ReceiveStream, encode)

            Console.WriteLine()
            Console.WriteLine("Response stream received")
            Dim read(256) As Char
            Dim count As Integer = sr.Read(read, 0, 256)

            Console.WriteLine("HTML...")
            Console.WriteLine()
            Do While count > 0
                Dim str As String = New String(read, 0, count)
                Console.Write(str)
                count = sr.Read(read, 0, 256)
            Loop
            Console.WriteLine("")
        Catch Exc As Exception
            Console.WriteLine()
            Console.WriteLine("The request URI could not be found or
was malformed")
        Finally
            If Not result Is Nothing Then
                result.Close()
            End If
        End Try

        The function runs through without error, but doesnt post
anything..im not sure why its not posting, the url and credentials are
fine.
        So I end up with 2 questions, one how to run a procedure to
post large xml files over http, and if anyone knows how to use
compression to reduce the file size sent?