Point Groups

I seem to have no problems creating them. But I can't seem to use them.
I've tried using point groups for contouring, and also for scaling point
attributes, and I get:
Command: pntenl
Scaling Multiplier <0.5>: 2
Select Carlson Software Point Attributes & Symbols to Enlarge/Reduce.
Select objects: g
Enter group name: topo
Invalid group name.
Enter group name:
I've tried using point groups for contouring, and also for scaling point
attributes, and I get:
Command: pntenl
Scaling Multiplier <0.5>: 2
Select Carlson Software Point Attributes & Symbols to Enlarge/Reduce.
Select objects: g
Enter group name: topo
Invalid group name.
Enter group name: