What the scanner says, and what each answer means

Every scan gets a card. Green is in; anything else says why.

• Valid. Let them in: good, they are in. The count moves. A guest-list pass gets the same.
• Ticket already used or Guest already checked in: this code has been scanned before. Either they walked back out and in, or the same ticket was forwarded to two people and the first one is already inside.
• Ticket is for a different event: a real ticket for a different night.
• Ticket not found or Invalid or expired QR code: not a shabanga code, or a screenshot of something else.
• Ticket has been refunded: it was refunded, and it no longer admits.
• Invalid PIN: the scanner was unlocked with the wrong event's PIN.

Modes matter. Door mode checks in admission tickets and guest passes. Counter mode redeems drink orders, Merch mode merch orders, and Credits mode credits orders; each refuses the other kinds and tells you which mode to switch to. An order scanned twice says Order already redeemed. A bar scan never checks anyone in at the door.