One simple way is to call a function that finds the shape on the slide, if it
exists.  It's probably more generally useful than just testing to see if the
shape exists or not; you may want to do something with the shape in other
macros, and the same function can be used to get the shape and work with it.

Say you're in a loop like:

Dim oSl as Slide
Dim oSh as Shape

For each oSl in ActivePresentation.Slides
 Set oSh = GetShape(oSl, "xyz") Then  
 If oSh Is Nothing Then   ' no shape by that name
    ' do your stuff here
 End If
Next   ' oSl

Function GetShape(oSl as Slide, sShapeName as String) as Shape
' Returns the shape named sShapeName on oSl
' or nothing if the shape doesn't exist
  On Error Resume Next
  Set GetShape = oSl.Shapes(sShapeName)
End Function

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