"Jerry W. Lewis" wrote in message
...
Thank you, that works; but is apparently yet another example where the C
API Excel4() function works differently than the corresponding Excel 4
macro function. Are these differences documented anywhere, or must they
be discovered by trial and error?

Welcome to the club. Microsoft documenation is just a rough guide, you need
to have a chat with your debugger to find out how things really work. Or if
you are feeling lazy, you can post your question to
microsoft.public.excel.sdk. :-)