The AutoNumber field makes an excellent primary key, and Access does not allow two AutoNumber data types in an Access table, only one. Add a new row to the table and name the field the name of the ...

Now I run into the problem of importing my old data while maintaining my table structure, namely the autonumber fields.

But if you want your autonumber field to start at 1 then you could just delete your current autonumber field and then put it back in again. That renumbered the autonumber field for me.