Where it says:

"The Group button is not available
The Group button may not be available if the shape, picture or object has been
inserted into a placeholder or you are trying to group a placeholder, as placeholders
can not be grouped with other shapes, pictures, objects. Move the shape, picture, or
object to another location on your slide outside of the placeholder or remove the
placeholder from the objects that you want to group."

Translation:  You're in a helicopter.

Doesn't do you a whit of good if you don't know HOW to move the shape/whatever out of
the placeholder, eh?  

Hint:  Ctrl+Drag the object to make a copy of it.  If it was in a placeholder,
chances are the new copy won't be.  Try ungrouping the copy.  If it works, delete the
original.

Also:  If the clip art is a bitmap picture rather than a bit of vector art, it can't
be ungrouped, in this or any version of PPT.  Or any other program for that matter.

-----------------------------------------
Steve Rindsberg, PPT MVP
PPT FAQ:  www.pptfaq.com
PPTools:  www.pptools.com
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