You didn't say what your operating environment is, but you might want to look at Thread #365567 ("BUG? TableUpdate is TRUE but no records written.") from 5/4/2000 and in particular Doug Hennig's reply in Message #366172. This pertained to a Novell network.

>I am experiencing a recurring and majorly annoying problem. Every once in awhile, a one of the tables used by my application just starting failing to retain new records added by the application. There is no error message as the records are inserted and committed, but in the end, they just aren't there. Recreating the table seems to end the immediate problem, but it seems sure to happen again eventually.
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>Does anyone know what might be causing this or how to avoid it?