Hi Jericho,
Just to also inform you; if you purchase any used Eventide processor and upon the attempt to register it as Italo describes, you discover that it is already registered, this means the original owner still has the unit registered. So you can do one of two things:
1. Contact the customer from who you purchased it and have them unregister it from their Eventide account
2. Contact Eventide Support, support@eventide.com, to have us be in touch with the person who still has the serial number registered to their account.
Congrats and enjoy!!