[help]

Option Strict On
Option Explicit On

Imports System.IO
Imports System.Net
Imports System.Text

Public Class Form1

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim cookieCon As New CookieContainer
        Dim request As HttpWebRequest = DirectCast(HttpWebRequest.Create("http://www.metin2.de/user/login"), HttpWebRequest)
        request.Method = "POST"
        request.UserAgent = "Mozilla/5.0 (Windows NT 6.0; rv:9.0.1) Gecko/20100101 Firefox/9.0.1"
        request.ContentType = "application/x-www-form-urlencoded"
        Dim post As String = "username=" & TextBox1.Text & "&password=" & TextBox2.Text

        Dim byteArr() As Byte = Encoding.UTF8.GetBytes(post)
        request.ContentLength = byteArr.Length

        Dim dataStream As Stream = request.GetRequestStream()
        dataStream.Write(byteArr, 0, byteArr.Length)

        Dim response As HttpWebResponse = DirectCast(request.GetResponse(), HttpWebResponse)
        Dim reader As New StreamReader(response.GetResponseStream())
        Dim seitenQuelltext As String = reader.ReadToEnd()

        If seitenQuelltext.Contains("Sicher") Then
            MsgBox("Account funktioniert!", MsgBoxStyle.Information)
        Else
            MsgBox("Account funktioniert nicht!", MsgBoxStyle.Critical)
        End If


    End Sub
End Class

        If seitenQuelltext.Contains("Login nicht erfolgreich. Benutzername oder Passwort falsch.") Then
            MsgBox("Login nicht erfolgreich!", MsgBoxStyle.Critical)
        Else
            MsgBox("Login erfolgreich!", MsgBoxStyle.Information)
        End If