>In a network with many users, eventualy save a document with tableupdate(.f.,.t.), eventualy 3 table is truncated and I need to repair.
>Records damaged show characters like pipes and I need to delete.
>
>I use BEGIN TRANSACTION before the TABLEUPDATE()
>
>Any help is apreciated
>
>Hapy new year
>
>Carlos Bermudez
>Guatemala

That sounds more like a network issue than a TABLEUPDATE() or BEGIN TRANSACTION issue. It can take as little as a bad NIC card to cause flaky problems like this. Do you have a network support person? It's probably going to be hard to catch because it sounds like the problem is sporadic, but it's worth a try.

Out of curiosity, what does Virtual Books do? If it's what it sounds like, that happens to be an emerging technology I am interested in.