Hi Jill.

>I have a large table, MASTER.DBF, with over 95,000 entries. The network is Win 2000, VFP 9.0, latst VMP.
>
>Some users are only updating data and one or two users may be creating new entries. Periodically (4 times in the last 2 weeks, since I've installed their system, here in Pohnpei, FSM), we have had a problem that the user entering new records is unable to save the entry. The user can log back in and make updates, but from then on no further new records can be added.

What is SET TABLEVALIDATE set to? If it's 0, you won't catch header corruption problems, which this sounds like (that explains why reindexing with SDT resolves the problem). Make sure it's a non-zero value so an error will be raised when this problem occurs. It doesn't solve the problem, but at least the user will know there's a problem rather than entering records and later finding them missing.

Doug