Set field problem--bizarre behavior Help!!

First some background. We have a multiple (>40 tables) file .fm5 database being served by FMserver to a mixed bag of macs and pcs. The server is an XServeG4.

Twice in the last couple of months, I've seen some odd and rather frightening behavior: scripts with a "Set Field" step don't work properly. The step "Set Field (othertable::fieldN, fieldA)", instead of setting FieldN in the other table to the value in FieldA in the current table, sets it to a value taken from a different field in the current table.

This seems to be function of the client machine, not the server itself, as it behaves quite properly using my own client.

It happened with both a Windows client (in that case I reinstalled FM6 on that client, which seemed to fix it) and once with a Mac client. In that case, the Mac client's home directory was on the server. When I had the user log off, then log on from a different machine, it seemed to fix the problem, ie, logging on from the original machine no longer exhibited the behavior.

So, does anybody have *any* idea about what gives here? You can see why it might be a scary problem. Most of my data entry people are savvy enough to recognize that a problem is occurring and come to me, but you can bet your life that somebody won't be paying attention some day.

I'm guessing it might be some sort of corruption of a local preference file. Should one be replacing those files on a regular basis?

I'm stumped.

Thanks in advance,

Carlisle