There is no direct code to get in the INN but you have to get a membership card. The code to get the membership card is 94000130 FCFF0000 621BFAF0 00000000 621BFAF0 00000000 B0000004 00000000 0000B600 EDB88320 2000B62C 00000008 D2000000 00000000
Action replay
The Harbor Inn in Canalave City is part of the mission to find and catch Darkrai. Nintendo has to give out the event-only item the Member's Card and when you have it in your bag - you'll be able to go into the Inn and then you'll fall asleep in the Inn and you'll wind up on New Moon Island where Darkrai resides.
The Harbor Inn in Canalave City from the Pokemon generation four games can only be opened with the Member Card. This item can only be obtained through an official Nintendo event.
You have to get the membership pass.
That was just a Mirage of the Pokemon Darkrai. You won't be able to see him again though but you can go into that inn any time after fighting/capturing Darkrai!
Action replay
in an event, you have to get the member's pass then go in the locked harbor at the top of canalave city above the pokemon center.
In Canalave City above the Pokemon center
In Pokemon Diamond, Pearl and Platinum Darkrai can be found on Newmoon Island. To get to Newmoon Island you need the Member Card for the Harbor Inn at Canalave City.
I'm Pretty sure you have to get the Darkrai card on a Mystery gift, but then again, I don't have an Action Replay, Sorry :(
In harbor inn
you need member pass you can get it using ar or event
A Membership Pass aka the Member's Card allows you access into the locked Harbor Inn in Canalave City. When you go into the Harbor Inn, you'll fall into a deep sleep and you'll wind up on Newmoon Island where you get a chance to battle and catch Darkrai.
You must get the Member's Card via Nintendo Event to get into the Inn in Canalave City.
you need a mystery gift
At the harbor inn at canalave city. You need a member pass which you can only get through a Nintendo event
The Harbor Inn in Canalave City is part of the mission to find and catch Darkrai. Nintendo has to give out the event-only item the Member's Card and when you have it in your bag - you'll be able to go into the Inn and then you'll fall asleep in the Inn and you'll wind up on New Moon Island where Darkrai resides.