Btrieve table update problem

Hi,

I'm developing an app. using Delphi (3.02) and Btrieve (6.15).

I started off using Paradox as a test database, just to get things
rolling but now I'm trying to swap to Btrieve: however, I can't get my
app. to start!

The problem occurs after I enter my Name and Password: the app. is
reading the right record in the right table but when I try to update it
(.CachedUpdates True, using TDatabase.ApplyUpdates), I get the message
'EDBEngineError: Couldn't perform the edit because another user deleted
or moved the record'.

I've examined the key field values (.Value, .NewValue and .OldValue)
immediately before and immediately after the .ApplyUpdates, and there is
no change.

I've built new persistent field components from the Btrieve table, but
this didn't make any difference.

However, when I swap back to using the Paradox database, the code works
fine.

Any suggestions?

Tia

Stuart