I am using Excel 2003 and I have been using the VBA code below on my computer
for a long time and find it extremely useful and which has never result in an
error.

A colleague asked if he could also have in on his computer and so I copied
it over. The strange thing is it doesn't seem to work on his computer and I
not sure why. I stops on the line 'Dim Result As New DataObject' that I have
higlighted with the *********. and a dialogue box appears saying: Compile
Error: User defined type not defined.

Does anyone know the answer why it works on my PC and not on his? I think it
might have something to do with declaring the DataObject

Sub AddSelection()

'This routine adds the values of selected cells and
'places the result in the variable 'SumOfRange'
'and also holds the value in the clipboard

Dim SumOfRange As Double
Dim Result As New DataObject '*******

SumOfRange = 0
SumOfRange = Application.WorksheetFunction.Sum(Selection) 'Add the Range

Result.SetText SumOfRange
Result.PutInClipboard

End Sub