Email Sockets Question

[iMaiden]

I am building a simple smtp server to receive email as follows:
Private Sub Listen()
Dim Listener As New TcpListener("25 ")
Dim sb As New SocketAndBuffer ()
Listening = True
Listener.Start( )
Do Until Listening = False

sb.Socket = Listener.Accept Socket()
sb.Socket.Begin Receive(sb.Buff er, 0, sb.Buffer.Lengt h, 0,
AddressOf ReceiveCallBack , sb)
Loop
End Sub

Private Sub ReceiveCallBack (ByVal ar As IAsyncResult)
Dim sb As SocketAndBuffer = CType(ar.AsyncS tate,
SocketAndBuffer )
Dim numbytes As Int32 = sb.Socket.EndRe ceive(ar)

Dim Receive As String = ASCII.GetString (sb.Buffer, 0, numbytes)
_count += 1

If _count = 1 Then sb.Socket.Send( "220 smtp.example.co m SMTP
server ready"*** this initial is the part I cannot figure out***)

MsgBox("receive " + Receive)
sb.Socket.Send( sb.Buffer)
Array.Clear(sb. Buffer, 0, sb.Buffer.Lengt h)
sb.Socket.Begin Receive(sb.Buff er, 0, sb.Buffer.Lengt h, 0,
AddressOf ReceiveCallBack , sb)

End Sub

I am able to telnet into my server and echo text but the server is not
able to send data to the client.
Any help is appreciated. TIA

[iMaiden]

Dim sr As New StreamReader(ns )
Dim returnedData As String = "220 smtp.sample.com SMTP
server ready"
Dim sw As New StreamWriter(ns )
sw.WriteLine(re turnedData)

iMaiden wrote:

I am building a simple smtp server to receive email as follows:
Private Sub Listen()
Dim Listener As New TcpListener("25 ")
Dim sb As New SocketAndBuffer ()
Listening = True
Listener.Start( )
Do Until Listening = False

sb.Socket = Listener.Accept Socket()
sb.Socket.Begin Receive(sb.Buff er, 0, sb.Buffer.Lengt h, 0,
AddressOf ReceiveCallBack , sb)
Loop
End Sub

Private Sub ReceiveCallBack (ByVal ar As IAsyncResult)
Dim sb As SocketAndBuffer = CType(ar.AsyncS tate,
SocketAndBuffer )
Dim numbytes As Int32 = sb.Socket.EndRe ceive(ar)

Dim Receive As String = ASCII.GetString (sb.Buffer, 0, numbytes)
_count += 1

If _count = 1 Then sb.Socket.Send( "220 smtp.example.co m SMTP
server ready"*** this initial is the part I cannot figure out***)

MsgBox("receive " + Receive)
sb.Socket.Send( sb.Buffer)
Array.Clear(sb. Buffer, 0, sb.Buffer.Lengt h)
sb.Socket.Begin Receive(sb.Buff er, 0, sb.Buffer.Lengt h, 0,
AddressOf ReceiveCallBack , sb)

End Sub

I am able to telnet into my server and echo text but the server is not
able to send data to the client.
Any help is appreciated. TIA