>Marcus,
>You might have a hardware problem with either your network cables or your hub. The latter caused ISO problems very similar to yours at one of my clients. The workstations with the problem were in a warehouse, and the constant temperature changes and dust/moisture wrecked the cabling a couple of times.

This is an extremely peculiar and nasty problem, at least for me. I think it's an odd mixture of network and local account configuration, and possibly something as you suggest with hardware. It also could be AV-related, but I cannot do anything about if it is, so am ignoring that, pretty much. It does still occur with AV temporarily disabled, anyway. Only seen it under NT4 SPs 4 to 6, never a problem with 95/98. I have two accounts on an NT4WS machine, a network and a local admin, either can connect to network. Here is the pattern of ISOs (I bring this up because I thought I had problem licked, but it has returned).

All this is running a large vfp app (vfp5 last year, and the past 6 months the vfp6 version) Smaller vfp apps do not seem to have the problem, but that is not much help:

1) Login with local machine admin account, data on machine - never an ISO
2) Login with local machine admin account, data on server - never an ISO
3) Login with network account, all data on machine - ISOs
4) Login with network account, data on server - ISOs
5) Login with network account, all data on machine, do not even connect to data server at all - ISOs

After 3 full scratch NT installs, the last one extremely carefully done, the problem disappeared completely for about 2-3 months (I tested a zillion times to be certain). But ISO errors have returned regularly in the past two weeks again, without any changes I am aware of, and I'm 100% sure they are not index-related. They hit on numerous code lines, though all are table-related. We cannot move to NT until this problem is resolved (although other non-vfp apps still have some NT problems also, so no one is moving yet, fortunately for me :) This testing is all on a Dell 300/64, I will get a faster/larger RAM test machine soon, and hope to get Win2K to test eventually. Weird problem, anyway, if anyone can shed any light...