So....did Main Menu option 12 Check For Updates - Registration Info now shows:
Product: JRiver Media Center Id 24.0.18 (Not Registered)
Registered to: UNREGISTERED - 30 days left in trial period.
How do I get this registered???
Did you licence this Id previously?
Take a look at menu option 18. (EDIT: the attached pic is for an IdPi but the NUC Id should look pretty similar)
Go to the Id board and check out the post entitled, "
Id Installation Instructions".
This information is normally provided somewhere in the details delivered to you, e.g. an email that includes stuff like, "Congratulations for choosing ... ". I suspect you've overlooked some of this.