Hi Rose,
Make sure you have the correct time and date set on the phone, having it a few months back would do more damage than good, lol if the clock is set to before it was even released then it wouldnt install...
Change the time and date to the correct settings and try again, I had the same error once on a N80 too but changed the date to the right date and it worked fine, I have installed the same version on the N80 and N73 quite a few times and havent really had any serious installation issues...
DigiTech, if its still asking for the activation code on the other phone, then its likely you still have the old maps on the memory card, format that card as well and try again