I am having problems with specific machines locking up while running our VFP6 EXE. Everyone is running NT4. The user still has control of the mouse, but other than that, the machine is locked up. Even CTRL+ALT+DEL has no effect, forcing the user to reset the machine. It has happened during transactions twice now, causing corrupted tables/indexes -- this concerns me greatly.

This EXE is now running on 15 machines, in 4 separate sites. The problem seems to occur on only 2 of the workstations (fortunately, one of them is here, where I can get to it). We are currently checking the cabling. Any other ideas?

Even the corrupted tables are strange. I can append to the table, but the application cannot insert (we use local views in a transaction). The Tableupdate occurs and transaction completes without generating an error. Then, I find that one or two tables do not contain the new records, although the other tables are correct. The corruption can be detected by record out of range errors:
FOR x=1 TO TAGCOUNT()
SET ORDER TO (x)
GO BOTTOM
ENDFOR