There... was a "U" you could have used, instead of a sideways "C"... *edit: never mind, read comments. *edit2: what's with the "M" on the top left? *edit3: why are the only letters in the message that are green, also spell "UN"— with the "U" being the one weird letter.

The magnetic letters which are on the table, in the background, implies that only the magnets you want are visible on the side of the vending machine. The only letter aside from the "W" and "M" that is red is a "Q".