License key from Macupdate - can't register an account with it on

I bought DTPro 2 from Macupdate waaaay back in 2015. Should I still be able to register on the Devon Technologies website with the license key I received from Macupdate? Its format is xxxx-xxxx-xxxxxx-xxxx-xxxx
When I try using the license key I’m told that the account is not found.


Unpersonalized licenses don’t have an account attached to them as there is no person that we could attached it to. But you can use your license for upgrading by using the menu command DEVONthink > Purchase License or Upgrade from inside the registered DEVONthink Pro 2.