Here is an article that describes the situation, see if it will help.
http://support.microsoft.com/default...roduct=acc2002
--
Wayne Morgan
MS Access MVP
"Giulio Simeone" <viandante20005@yahoo.it> wrote in message
news:84865ca4.0405140254.432077b5@posting.google.c om...[color=blue]
> Hello,
> I am using Windows 98 and Access XP and I have noticed the following
> strange thing. When I add a new record to a table, sometimes the
> counter is correctly set to the highest counter in the table plus 1,
> sometimes it is set to 2, 3, 4, 5, ... even if in the table there are
> already this counter values. In this last case, in fact, it is
> generated a duplicate key error.
>
> The properties of the counter field are set to 'Autoincrement' and
> 'Duplicates not admitted' in either cases.
>
> Why does Access behave sometimes in one way, sometimes in another way?
>
> Excuse me for my approximate English!
>
> Thanks,
>
> Giulio Simeone[/color]
