Thanks for the explanation, Chip.
By the way, I love your website - that's an astounding collection of
Excel support materials.

Darren

Chip Pearson wrote:
Application.Caller can be used only in Function procedure that was
called from a worksheet cell (in which case it returns a Range reference
to the cell(s) from which the function was called), or in a procedure
called via the OnAction property of a Shape object (in which case it is
a String value containing the name of the Shape). In any other context,
Application.Caller is an Error-type Variant containing a #REF error value.