A family of Microsoft relational database management systems designed for ease of use.
Hi Steffen,
Try the following in the onclick or after update event of your check box:
If Me.CheckBoxName = True Then
[Forms]![MainFormName]![SubFormName]![FieldName].ColumnHidden = True
Else
[Forms]![MainFormName]![SubFormName]![FieldName].ColumnHidden = False
End If
Replace the bolded names with your own.