>Hi Al:
>
>I really thank you for your reply. I noticed there's no solution. You were the only one. Rest made a significant silence... I thought the worst...
>
>What's "TS"?

"Terminal Services", now called Remote Desktop Services (RDS):

http://en.wikipedia.org/wiki/Remote_Desktop_Services

>
>I wrote not SQL, no famous (reliable) net software (as W NT or Novell) and I pointed to "plain windows". As I was reading you the laugh was going around my stomach... It's very hard to convinced many of my clients to buy a PC and you pretend they buy a good computer for a "reliable" net????
>
>VFP has any function that tells me if a file is open by another user (I think) and I thought there should be a magic function that returns if a file open is not available any more.

There are too many things that can go wrong if a computer crashes or a network connection is broken. I know of no reliable method to handle all of the possible errors that could arise.

>
>I few years ago I had a client who used a W NT server and workstations with W 95. Sometimes they have any problem of conection but IT WAS AN OFFICE. A quiet office. (it means not-working people) they called me. I said "unplug and plug the net wire" and the problem solved (but the program hanging of course)
>
>The problem I thought is a supermarket. 1,2,3 or more (but not too many more) sales points. There's lots of people snorting because of the hanging. There's a lovely cashier remembering me but not as I'd like she does.
>
>I think (hope) you undestand.

Going back to the idea of RDS, maybe this is a business opportunity for you. If your clients' networks are unreliable, you could set up a RDS server at your offices, accessible from the Internet. Then, you could let remote users run the program on your server.

If their computers or network crash, they can log back in to your server after they get it fixed. No data loss, no corruption.

Of course, that depends on the availability of at least good-quality dial-up Internet connections, and preferably high-speed Internet.