Ribbon menu button disable enable.

Hi
I made a exampel file of the ribbon
There is one thing i don't understand.
I can enable one control with the following code
When i trye the same code like for enable for disable it not working

Sub EnableControlsWithCertainTag3()
'Enable only the control with this Tag "Group1Button1"
    Call RefreshRibbon(Tag:="Group1Button1")
End Sub

The only thing i found until now is disable all controls

Sub DisableAllControls()
'Disable all controls
    Call RefreshRibbon(Tag:="")
End Sub

How to disable one crontrol ?