Michael, Thank you.

My aplication has a variable window caption.
So I'm thinking about using SYS(5)+SYS(2003) as a mutex name.
Unfortunately, code in this article seems to be incomplete: I don't have FoxPro advisor.

Is the mutex released automatically by OS if C5 error occurs at my VFP
application startup ?

>Check this out. http://www.advisor.com/Articles.nsf/AID/TASKG05
>I've used it without trouble in VFP6 no idea about VFP7. Guess only George himself can say.
>
>HTH
>Mike