This article discusses several possible reasons for this:
Fixing AutoNumbers when Access assigns negatives or duplicate
at:
http://allenbrowne.com/ser-40.html
--
Allen Browne - Microsoft MVP. Perth, Western Australia
Tips for Access users -
http://allenbrowne.com/tips.html
Reply to group, rather than allenbrowne at mvps dot org.
"J. S. EDV" <(E-Mail Removed)> wrote in message
news:F4AEA480-F51E-4718-8058-(E-Mail Removed)...
> Good morning NG,
>
> the ID-field in an Access table, which should increment every new record,
> resets sometimes its auto-value counter to a number which has been already
> assigned. When I correct this through a new record which contains an
> explicit
> ID-value, which is higher than the highest which has been assigned, the
> allocation of new ID-values seems to work for some records. But after some
> new Records the problem occurs again.
>
> Does anybody know a solution for this?
>
> Thanks
>
> Jacek