Referencing another Workbook
 

Within a sheet I can enter a cell of the format:

[ ] = [Book1]Sheet1!A1

When I do this all works well. So then I went ahead and used it
extensively in a macro.

The problem is that this always works properly when I use it directly on
a spreadsheet, but it only works in the macro if I've already opened up
the other workbook within Excel. Somehow a sheet knows to go find the
book if it's not already open, but the macro just throws up it's hands
and fails.

Have I overlooked some step necessary to make this work in a macro?
(incidentally I'm using Excel97 if that makes any difference)

Thanks....

Bill