Chance1234,
IF your database is not split, and/or you have a large
amount of existing data, below may be the quickest
"one table at a time" method. Otherwise, someone will
point you to an easier method using an add-in or code.
To absolutely reset an autonumber field: If the autonumber
is a part of a relationship as a primary or foreign key,
delete (temporarily) the relationship. Next, open the
table in design view. Select the field. If a primary key,
deselect key icon. Cut (NOT Delete) selected autonumber
field, insert a blank row, and paste autonumber field back
again. Save and close table.
Repeat for related table(s) if other autonumbers involved
to reset them also (otherwise these related autonumber
fields may not match up). Finally, restore relationship as
it was a few minutes ago.
Hope this was helpful.
John