Instructions
Turn on the PSP and navigate to "Settings." Pick "Network Settings" and press "X."
Select "Ad Hoc Mode" and a specific communication channel. Ensure each other PSP unit is set to the same channel or cooperative play will not work. Do not choose "Automatic" since you cannot specify the channel for each unit.
Press "X" to save your settings. Select the game icon to go back to the home screen and start "Harry Potter and the Goblet of Fire."
Select "New Game" and then press "X." Select one of the players to control and then press "X." Only one player can choose a character per level. Cooperative players can join the game at any part of the mission.