The ARP table generates itself whenever you try to talk to an unknown IP address. This happens automatically, at a level so deep that TCP/IP never needs to worry about it. Just delete the bad entry to make room for the new one, and the new entry will just appear next time you try to use the printer.

Deleting an ARP entry is a very safe thing to do. You can't even break connections with it, any missing ones will just be looked up again.