Dear Keith,
Just File|SaveAs each cardfile, one at a time as another name. Then delete the original cardfile in the File|Open Dialog by right-clicking on it and choosing delete.
When you SaveAs, the original cardfile remains and you save a copy, so you need to delete the original to avoid having 2 identical cardfiles.
HTH
Regards Jim
Check the FAQ area of this Forum for answers (If there are any FAQs!) , it could save you a lot of time and effort!