Error when POST and GET via Sockets .NET

Question

I'm trying to post to an ASP.NET Site via Sockets by sending the Raw HTTP Request information however; when trying to read the response I get

"Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host."

Here is the code I am using

Public Function PerformGetRequest() As String
    Dim strResponse As String = String.Empty
    Dim GetRequest As New System.Text.StringBuilder
    Dim lStreamWriter As StreamWriter = Nothing
    Dim lStreamReader As StreamReader = Nothing
    Dim lNetworkStream As NetworkStream = Nothing

    GetRequest.Append(String.Format("GET http://{0}/default.aspx HTTP/1.1{1}", mstrHost, vbCrLf))
    GetRequest.Append(My.Settings.HTTPAcceptString & vbCrLf)
    GetRequest.Append(My.Settings.HTTPAcceptLanguageString & vbCrLf)
    GetRequest.Append(My.Settings.HTTPUserAgentString & vbCrLf)
    GetRequest.Append(My.Settings.HTTPEncodingString & vbCrLf)
    GetRequest.Append(My.Settings.HTTPConnectionString & vbCrLf)
    GetRequest.Append(String.Format(My.Settings.HTTPHostString, mstrHost & vbCrLf))

    Try

        If Not mTcpClient.Connected Then
            mTcpClient.Connect(mstrHost, 80)
        End If

        If Not mSocket.Connected Then
            mSocket.Connect(mstrHost, 80)
        End If

        lNetworkStream = mTcpClient.GetStream()

        lStreamReader = New StreamReader(lNetworkStream, True)
        lStreamWriter = New StreamWriter(lNetworkStream)
        lStreamWriter.WriteLine(GetRequest.ToString)
        lStreamWriter.Flush()

        strResponse=lStreamReader.ReadToEnd()

    Catch ex As Exception
        Throw New Exception(ex.Message)
    End Try

    Return strResponse

End Function

The exception occurs at the lStreamReader.ReadToEnd line.

Thanks in advance for any assistance.