Sub Probleme()
        Me.SqlConnection2.Open()
 
        Dim strSQL As String
 
        strSQL = "select * from Tbl_Kategorie where Ebene = '1' ORDER BY" & _
          "Kategorie"
 
        Dim dbCommand As New SqlClient.SqlCommand(strSQL, Me.SqlConnection2)
        Dim dbReader As SqlClient.SqlDataReader = dbCommand.ExecuteReader( _
          CommandBehavior.CloseConnection)
 
        While dbReader.Read
            TN1 = TreeView1.Nodes.Add(System.Convert.ToString(dbReader.GetValue( _
              dbReader.GetOrdinal("Kategorie"))))
        End While
 
        dbReader.Close()
        Me.SqlConnection2.Close()
        RichTextBox1.Rtf = ""
        RichTextBox2.Rtf = ""
        Call UnterProbleme()
 
 
    End Sub
 
    Sub UnterProbleme()
        Dim strSQL As String
        Dim Ausgabe
        Dim Übergabe
 
        '__________________________________________ Hier wird die ID - 
        ' ausgelesen____________________
        For Each TN1 In TreeView1.Nodes
            Me.SqlConnection2.Open()
            Ausgabe = TN1.Text
 
            strSQL = "select * from TBL_Kategorie where Kategorie = '" & _
              Ausgabe & "'"
 
            Dim dbCommand As New SqlClient.SqlCommand(strSQL, Me.SqlConnection2)
            Dim dbReader As SqlClient.SqlDataReader = dbCommand.ExecuteReader( _
              CommandBehavior.CloseConnection)
            If dbReader.Read() Then
 
                Übergabe = (System.Convert.ToString(dbReader.GetValue( _
                  dbReader.GetOrdinal("ID"))))
                dbReader.Close()
                Me.SqlConnection2.Close()
            End If
            dbReader.Close()
            Me.SqlConnection2.Close()
            '________________________ Bis hier 
            ' _________________________________________________________
 
            If Übergabe = "" Then
                GoTo start
            End If
            '________________________ Bis hier überprüfung 
            ' _________________________________________________________
 
            '__________________________________________ Hier wird die 
            ' Unterkategorie - ausgelesen____________________
            Me.SqlConnection2.Open()
 
            strSQL = "select * from TBL_Kategorie where Parent = '" & Übergabe _
              & "'"
 
            Dim dbCommand1 As New SqlClient.SqlCommand(strSQL, _
              Me.SqlConnection2)
            Dim dbReader1 As SqlClient.SqlDataReader = dbCommand1.ExecuteReader( _
            CommandBehavior.CloseConnection)
            'Dim knot2 As String
 
            Do While (dbReader1.Read)
                ' Hier wird einfach alles dem gesuchtem Node zugeordnet
                TN1.Nodes.Add(System.Convert.ToString(dbReader1.GetValue( _
                  dbReader1.GetOrdinal("Kategorie"))))
                Weiter12 = (System.Convert.ToString(dbReader1.GetValue( _
                dbReader1.GetOrdinal("Kategorie"))))
                knot2 = (System.Convert.ToString(dbReader1.GetValue( _
                dbReader1.GetOrdinal("id"))))
                Call Unter_Unter(knot2)
            Loop
            dbReader1.Close()
            Me.SqlConnection2.Close()
        Next
 
 
start:
 
    End Sub
    Sub Unter_Unter(ByVal knot2 As String)
        Dim strSQL As String
        Dim Ausgabe
        Dim Übergabe
        ' Ausgabe = TN1.Text
        ' __________________________________________ Hier wird die ID - 
        ' ausgelesen____________________
        Dim TN1 As TreeNode
 
        '    For Each TN1 In TreeView1.Nodes
 
 
 
        Next
 
        '________________________ Bis hier überprüfung 
        ' _________________________________________________________
 
        '__________________________________________ Hier wird die 
        ' Unterkategorie - ausgelesen____________________
 
        Me.SqlConnection4.Open()
 
        strSQL = "select * from Tbl_Kategorie where Parent = '" & knot2 & "'"
 
        Dim dbCommand1 As New SqlClient.SqlCommand(strSQL, Me.SqlConnection4)
        Dim dbReader1 As SqlClient.SqlDataReader = dbCommand1.ExecuteReader( _
          CommandBehavior.CloseConnection)
 
        'If dbReader1.Read() Then
        Do While (dbReader1.Read)
            TN1.Nodes.Add(System.Convert.ToString(dbReader1.GetValue( _
              dbReader1.GetOrdinal("Kategorie"))))
        Loop
        'dbReader1.Close()
        Me.SqlConnection4.Close()
        'End If
        dbReader1.Close()
 
        Me.SqlConnection4.Close()
        Next
start:
 
    End Sub

sch?n wenn man sich helfen kann