Tlg1261,
Thanks for the further explanation.
First of all, the alpha prefix and the number portion of the barcode
need to be in separate fields in your table. Then, does each Series
have some sort of identifier, a series code or some such? If not, you
should arbitrarily assign one, and put a field for this also in the
cards table. It will make things easier if you have a Series table,
where you list all the series. If the SeriesID is meaningless, you can
use an AutoNumber.
Then, I would set it up this way... Put your form for entry of these
Cards records as a subform onto a form based on the Series table, with
the SeriesID as the Link Master Fields / Link Child Fields properties.
For the first Card in each Series, you can simply manually enter the
starting number. Then, you can assign a macro on the Before Insert
event of the Cards form, using a SetValue action, to set the value of
the barcode number field to the equivalent of...
DMax("[BarcodeNumberField]","CardsTable","[SeriesID]=" & [SeriesID])+1