Dim chk As CheckBox
        Dim pan As Panel
 
        For Each con As Control In Me.TabPage3.Controls
            If TypeOf (con) Is CheckBox Then
                chk = CType(con, CheckBox)
                pan = CType(con, Panel)
                If chk.Text = "Nicht def." Then
                    chk.Enabled = False
                    pan.BackColor = Color.Red
                Else
                    chk.Enabled = True
                    pan.BackColor = Color.Lime
                End If
            End If
        Next con

mfg
rt