>Anyway, they got it installed on another of their NT machines, so I still figure it has to do with the CDFS.SYS file on that machine that is messing up NT's ability to properly read the CD.

I've had this happen on only one NT machine out of well, many 100s or even 1000s of NT installs. We finally installed via a WAN, which was inconvenient, but worked. Problem very rare, but it can happen. I think you're on the right track, anyway...

One way I isolated the problem was to find another non-vfp cd-install that wouldn't install right either.