>I have had a few problems in the recent months regarding C0000005 errors. The most recent that I have tracked down, was due to repeated SET("index") statements. According to the MS Knowledge base(Q221737), this has been fixed in SP3. I've had SP3 installed since I first installed VFP on this machine(NT4 Workstation). Is there any way that SP3 could have been messed up on this machine, using older files? Or even just at my client's sites? Please LMK if you have any ideas. Thanks.

Sure, it's possible. If someone else's older vfp app is installed, for example. This can particularly occur across many machines if a network does an SMS delivery install with an older application, and the SP3 DLLs are overwritten.

Usually just comparing the size of vfp6 DLLs will determine whether there's a version mismatch.