Follow-up question to the post "Determine if a workbook is already open":

Given:
- At least two excel instances running. Only two are of interest, call them
A and B
- Excel instance B has a workbook open that I want to access for
manipulation, call it TargetWkbk
- Excel instance A has VBA code that I am executing... it knows that the
TargetWkbk is not open in this Excel instance (i.e. A) but that the
TargetWkbk is open somewhere (this is what I learned todo from the previous
post)

My Question:
How can I get a reference (handle?) to Excel instance B so that I can
manipulate (read, write) its contents from the VBA code in Excel instance A?

Thanks for any thoughts...

Charles