>Dear All,
>
>the client PC had installed with the correct runtime, else, if u installed the program with installer, the program will not work. The only difference is Program can open if installed using installer. But if just directly copy the Program from other PC, it won't open.
>
>thanks

Just want to check if this is the situation as you describe:
1. If you install the program using an installer the program works OK
2. if you simply try to copy the EXE over to the computer you get the error as described

If this is indeed the case, then you might have the following:
* Client's computer already has VFP runtime -- but one that doesn't match (it could be a different version, or perhaps relating to patches made by software such as ReFox -- some protection level requires a patched runtime)
* When you use the installer, perhaps the runtime is being copied and registered - overriding what was already on the client's computer.

You can try to copy the required runtime files from your development environment along with the EXE -- see if the program runs as expected, if the error continues. I'd run into bizarre errors on a customer's computer -- turned out that the IT personnel did install the VFP runtime of the correct version, but of an earlier revision (i.e. earliest release w/o any service packs). Updating the runtime library to most current revision (that includes all the service packs) corrected the problem.