Pat,
Yes, data path is fairly important.
oProp.AppStartPath=JUSTPATH(APPLICATION.SERVERNAME)+"\"
is the key line. It specifies the physical path wherever the mtdll is. Then I SET DEFA to this and don't worry about it any more. I think this will work for any file, not just DBFs.
>Never mind - I found the problem. I had commented out the line in avfpinit that set the data path because I was getting an error on that line when running on the test machine. I'll have to look into that now...