Add an unbound control to the detail section.
Set it's control source to:
=1
Set it's RunningSum property to Over Group.
Name this control "CountGroup"
You can make this control Not Visible.
Code the Group Footer Format event:
If you have no other control's to show in the Group Footer:
Cancel = [CountGroup] = 1
If you do want the Group Footer to show but just not the Total
control, then use:
Me.[TotalControl].Visible = Not [CountGroup] = 1