If you originally purchased the software before the Factorytalk activation scheme was implemented, then there will be a master floppy for RSLogix 5000. Your v16 may have been updated a number of times, but the original EVRSI copy protection still applies. And you have to install and/or reset the license with the move and reset utilities.
If on the other hand, you purchased the software after Factorytalk activation scheme was implemented, then the product key and serial number is in a red envelope.