Esta função lhe permite determinar qual será o próximo número gerado no campo AutoNumber:
Para que funcione, habilite a biblioteca Microsoft ADO Ext. for DDL and Security (ADOX) no menu Ferramentas > Referências na janela do VBA.
Function ChangeSeed(strTbl As String, strCol As String, lngSeed As Long) As Boolean
'You must pass the following variables to this function.
'strTbl = Table containing autonumber field
'strCol = Name of the autonumber field
'lngSeed = Long integer value you want to use for next AutoNumber.
Dim cnn As ADODB.Connection
Dim cat As New ADOX.Catalog
Dim col As ADOX.Column
'Set connection and catalog to current database.
Set cnn = CurrentProject.Connection
cat.ActiveConnection = cnn
Set col = cat.Tables(strTbl).Columns(strCol)
col.Properties("Seed") = lngSeed
cat.Tables(strTbl).Columns.Refresh
If col.Properties("seed") = lngSeed Then
ChangeSeed = True
Else
ChangeSeed = False
End If
Set col = Nothing
Set cat = Nothing
Set cnn = Nothing
End Function