Hugo,
>
>But, if I understand correctly (most of the time not) this works fine if the user is trying to run the application from the same machine, but it is still possible to run the application more than once from different machines.

This may seem terrible thick or stupid, but if you wanted to keep an application from being run on multiple workstations, why install it on more than one?

>Is there any solution other than having a locked shared file across the network?

There might be, such as calling the api to see if the file was currently opened on the network.

>Can that solution be used with different flavors of Foxpro (VFP, FPD, FPW)?

No. Then again, I'm not concerned with implementing a solution in an earlier version, especially in view of the fact that I'm converting all my applications to VFP from FPW just as I had previously converted from FPD. Once converted, I don't support previous versions.

>I am asking not to be controversial (is that the word?) but because we are using it in real life, we ran several unatteded programs (in all that foxpro versions) and I am wondering if there is a better way to avoid running them more than once in different machines.
>
The word is OK and you're not being so. Under the circumstance you describe, there isn't a way that I could think of to accomplish the goal. The reason being that you're dealing with applications targeted at three very different platforms: DOS, Win16 and Win32.