boldHow to determine who has an excel 2000 file open

[sebpas]

I'm running an access program that updates 2 excel files with results from sql queries. I would like to know how to determine if either of the excel file is open (with locks)and if so, who has it open. That way I can inform the user of the access program with a msgbox who's the guilty one.
I've seen it done before, just don't know wich language and methods they used.
Thanks