Tcp-chat ohne server -- Probleme bei den Ports

#include <GUIConstantsEx.au3>


GUICreate("Chat", 1000, 1000)
GUISetBkColor(0x00000)
$mainedit = GUICtrlCreateEdit("Chat gestartet - Warte auf Verbindungsaufbau!", 50, 50, 750, 750)
$Sendbut = GUICtrlCreateButton("Send", 820, 820, 50, 50)
$savebut = GUICtrlCreateButton("save-chat", 820, 50, 100, 50)
$SendInputBox = GUICtrlCreateInput("", 50, 820, 750, 50)
GUISetState(@SW_SHOW)
Sleep(1000)
GUICtrlSetData($mainedit, GUICtrlRead($mainedit) & @CRLF & "Your Ip is " & @IPAddress1 & "!")


Dim $Ip = InputBox("Set Your Partners IP!", "Please Enter your Partners IP!", "Enter IP here!")
GUICtrlSetData($mainedit, GUICtrlRead($mainedit) & @CRLF & "Partner's IP is " & $IP & "!")
Sleep(1000)
Dim $Port = 1200
GUICtrlSetData($mainedit, GUICtrlRead($mainedit) & @CRLF & "Port is " & $Port & "!")


TCPStartUp()
Sleep(500)
GUICtrlSetData($mainedit, GUICtrlRead($mainedit) & @CRLF & "TCP is switched on!")
Sleep(200)




$Connect = MsgBox(4, "Connecten oder connecten lassen?", "Drücke Ja um dich selbst zu connecten und Nein um dich connecten zu lassen!")


If $connect = 6 Then
	;-----------------------------------
	GUICtrlSetData($mainedit, GUICtrlRead($mainedit) & @CRLF & "TCP is connecting")
	$Socket = TCPConnect($IP,$Port)
	Dim $String, $msg, $empf, $Sended
	If @error Then
		MsgBox(0,"Error", "Verbindung Fehlgeschlagen! Überprüfe die Ip des Chatpeartners!")
		MsgBox(0,"Error", "Error: " & @error & " .")
	EndIf
	;-----------------------------------
EndIf


If $connect = 7 Then
	;------------------------------------------------
	GUICtrlSetData($mainedit, GUICtrlRead($mainedit) & @CRLF & "Tcp is waiting for incoming connections...")
	$Mainsocket = TCPListen($Ip, $Port)
	Dim $Socket = -1


	Do
		$Socket = TCPAccept($Mainsocket)
	Until $Socket > -1 or $Socket < -1
	Dim $msg, $recv, $Sended


	;------------------------------------------------
EndIf


GUICtrlSetData($mainedit, GUICtrlRead($mainedit) & @CRLF & "Connected!")
TrayTip("Verbunden", "Du bist verbunden mit " & $IP & "!", 4000)
Sleep(2000)
GUICtrlSetData($mainedit, GUICtrlRead($mainedit) & @CRLF & "You can Chat now!")
SoundPlay(@WindowsDir & "\media\tada.wav",1)
GUICtrlSetData($mainedit, GUICtrlRead($mainedit) & @CRLF & "_______________________________________________" & @CRLF)


While 1
   $msg = GUIGetMsg()
       	Select
        	Case $msg = $GUI_EVENT_CLOSE
            	ExitLoop
        	Case $msg = $SendBut
				$String = GUICtrlRead($Sendinputbox)
				$Sended = TCPSend($Socket, $String)			
    	EndSelect
	$empf = TCPRecv( $Socket, 10000)
	If $empf <> "" Then GUICtrlSetData($mainedit, GUICtrlRead($mainedit) & @CRLF & $IP & "  -->  " & $empf)
	If $Sended <> "" Then
		GUICtrlSetData($mainedit, GUICtrlRead($mainedit) & @CRLF & "You" & "  -->  " & $String)
		GUICtrlSetData($Sendinputbox, "")
    	$Sended = ""
	EndIf
		If @error Then ExitLoop
WEnd





TCPShutDown()