I don't know of an explanation, but Stephen Bullen has sample code that
enumerates all windows - you could adapt this to identify those windows
which represent excel applications.

http://www.oaltd.co.uk/DLCount/DLCou...le=EnumDlg.zip

This is found on
http://www.oaltd.co.uk/Excel/Default.htm

as the last item under "they said it couldn't be done" section.

--
Regards,
Tom Ogilvy

"noel mcwilliam" <noel wrote in message
...
Hi People, Can anyone help?

I would like my macro to detect whether other excel applications are open
on
my PC. As far as I can tell there is no applications collection ao I'm
guessing (!) that it'll necessitate an API call? ...which leads me to my
second question: is there any literature that gives a good overview of the
api - I'd like to become familiar with it but the on-line documentation on
the msn website is a bit daunting!

Many many thanks in advance

Noel