Använd SELECT @@IDENTITY
ex.
<%
Set Connect = Server.CreateObject("ADODB.Connection")
Connect.Open "Provider=Microsoft.Jet.OLEDB.4.0;Data Source ="& Server.MapPath("databas.mdb")
Connect.Execute("INSERT INTO tabell1 (fält1, fält2) VALUES('värde1', 'värde2')")
Set RecSet = Connect.Execute("SELECT @@identity")
strID = RecSet(0)
RecSet.Close : Set RecSet = Nothing
Connect.Close : Set Connect = Nothing
%>