Private Sub F_Main_Load(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles MyBase.Load
        LadeTab()
    End Sub

    Private Sub LadeTab()
        Try
            conn.Open()
 
            ds.Clear()
 
            da.Fill(ds, "Users")
 
            cboUsername.DataSource = ds
            cboUsername.DisplayMember = "Users.Username"
            cboUsername.ValueMember = "Users.ID"
 
            'With Me
            '.txtUsername.DataBindings.Add("Text", ds, "Users.Username")
            '.txtPasswort.DataBindings.Add("Text", ds, "Users.Passwort")
            '.txtEmail.DataBindings.Add("Text", ds, "Users.Email")
            'End With
 
        Catch ex As OleDbException
            MessageBox.Show(ex.Message, "Fehler", MessageBoxButtons.OK, _
                MessageBoxIcon.Exclamation)
        Finally
            conn.Close()
        End Try
    End Sub

Private Sub UpdateTab(ByVal strUser As String)
 
        Dim cb As OleDbCommandBuilder = New OleDbCommandBuilder(da)
 
        If MessageBox.Show("Sollen die Daten geändert werden?", _
            "Daten ändern?", MessageBoxButtons.YesNo, _
            MessageBoxIcon.Question) = DialogResult.No Then
            Exit Sub
        End If
 
        Try
            conn.Open()
            Dim row As DataRow
            Dim dt As DataTable = ds.Tables("Users")
 
            For Each row In dt.Rows
                If row!Username = strUser Then
                    row!Passwort = txtPasswort.Text
                    row!Email = txtEmail.Text
                    row!Datum = DateTime.Now.ToShortDateString
                End If
            Next
 
            da.Update(ds, "Users")
 
            MessageBox.Show("Datensatz geändert!", "Update", _
                MessageBoxButtons.OK, MessageBoxIcon.Information)
 
        Catch ex As OleDbException
            MessageBox.Show(ex.Message, "Fehler", MessageBoxButtons.OK, _
               MessageBoxIcon.Exclamation)
        Finally
            conn.Close()
        End Try
        LadeTab()
    End Sub