>To all the Gurus that have helped me so many, many times in the past years...I have yet another problem.
>
>Scenario: We have an application dealing with auto repair shop operations installed throughout Northern CA. Written entirely in VFP 7 (originally ported from 2.6...an old program...anyway) which runs on a variety of Windows (depending on the shops) from 98, XP, 2000, the dreaded ME, etc. The servers are anything from XP, NT, 2000, or Novell 3.x or 4.x.
>Now...Everything has been smooth for years except for one shop in the last couple months.
>
>Their platform:
>14 Workstations running XP PRO, 2 Workstations running Windows 2000, all attached to a Novell 4.11 Server on which the VFP 7 application resides.
>Everything was running smoothly then one machine started intermittently (very intermittantly) getting the Fatal Exception Error C0000005 and not so graciously failing. Then another started the same symptom. Now two machines are acting up. This continues cascading for weeks. Now all machines exhibit th8is same behavior.
>
>Symptoms:
>It seems to only occur (according to them) during one particular operation during the program, that is, looking up a customer's or vehicle's history. For instance: Jane Doe walks up to the front counter and asks to have her car smogged. John pulls up her car on the screen and checks the history table to see when she was last smogged. BAM and Lock Up. It doesn't seem to matter who the customer is, which car, which operation, which computer, etc.
>
>We have tried reinstalling VFP runtime(s) on all machines, Windows on all machines, new machines...problem is still there and seemingly progressing albiet still intermittently and still (in my opinion) slowly (but I am not the frustrated technician either).
>
>By the way. The same version of the application is running flawlessly in all other shops which is starting to lead me to believe it is in their data somehow?
>
>It seems to me there was a similar problem years ago with Windows95, DCOM, and VFP3? and that it was a Microsoft System related thing but I cannot for the life of me find it anymore.
>
>Any ideas on how to proceed would be greatly appreciated.

It sounds like a subtle data corruption issue. I would do the following, in order:

1. Check the data tables for indications of corruption - often this will show up as ASCII characters outside the normal range (high or low), or CHR(0). Fix as required.

2. Rebuild table indices i.e. DELETE TAG ALL followed by INDEX ON ... Note that REINDEX will not fix subtle index corruption as it re-uses index header information (which may be corrupt) to rebuild the tags. You will need to take extra steps if the tables are in a .DBC and related as these depend on the index tags and may be lost on DELETE TAG ALL.

3. If that doesn't fix the problem you might try getting hold of VFP9 which has built-in checking which is more stringent that in earlier versions. Merely trying to open a table in VFP9 might point up the problem.

Adding a redistributable utility like SDT to your app might be an inexpensive way to avoid these problems in the future.