Santy

> As you see, there is no "Table.Cancel" to try again from the begining
after
> the error, so there still is an active record in edit/insert state, WHILE
> ComputerB is calculating a new number.

If you look at my other message Computer B must be prevented from
calculating a new number until Compter A has finished posting.  Even if
there is no error a duplicate could occur.

John

Santy,

<< Please notice that numbers are no saved in a simple field. There will be
a new record for each number. For example: >>

I know, and  I'm suggesting that you change your database and code.  Trying
to work on the basis of grabbing the last row's number is a recipe for
failure without using a transaction because you cannot protect the table
adequately when only using something that can be bypassed by using another
application like DBSYS, for example.

--
Tim Young
Elevate Software
www.elevatesoft.com