Long time ago I have created a VBA code in which I create several
graphs from data in worksheets. It was developed and is still working
in Excel 2003.

Now with Excel 2007 and Excel 2010 Beta I get

Run-time error '13':
Type mismatch

when program control reaches the line:

Set graf = list.ChartObjects(1).Duplicate

The variables are explicitly declared with:

Dim list As Worksheet, graf As ChartObject

Any ideas how to solve the problem?

TIA, Primoz