Hi,
In addition to Martin's suggestions run a PACK DATABASE prior.

>Hi everyone
>
>I have this problem since VFP 8, actually. Whenever I try to add RI code in a dbc, no matter what DBC is it, as soon as I press Ok in RI Builder, the database gets corrupt and I am receiving "DBC consistency error". After validating the database, some times I can use the database, sometimes it gets trashed completely.
>
>Did anyone see this behavior? Is there anything I can do to make it stop?