Note that some controls do not have an Enabled property (for example, Shape controls) so the program must use an On Error statement to protect itself.

Note also that you can disable the entire form by setting its Enabled property to False. Unfortunately that disables everything on the form including the form's system menus so the user cannot close it. The form's controls also look like they are enabled even though the user cannot interact with them.

Similarly you can disable the controls inside a Frame by setting the Frame's Enabled property to False but the controls still look enabled.

' Enable or disable the form's controls.
Private Sub EnableControls(ByVal frm As Form, ByVal _
    enabled_state As Boolean)
Dim ctl As Control

    ' Examine every control.
    For Each ctl In frm.Controls
        ' Don't disable the form's CheckBox or the user
        ' won't be able to reenable it.
        If Not (ctl Is chkControlsEnabled) Then
            On Error Resume Next
            ctl.Enabled = enabled_state
            On Error GoTo 0
        End If
    Next ctl
End Sub