You use it in the Galactic Eterna building on the first floor in the upper left-hand corner.
well you need the secret key for team galactics HQ
stop being a Pokemon playin douche
you use th key in the eterna city galactic biulding between the book case and wall
I believe that you go to the kitchen in the Old Chetau.
There is a cheat for obtaining the Secret Key. You can use Action Replay Codes for WI-Fi Event Items.
you use the Wirless conections
you need to go to an event
Go to http://www.serebii.net/platinum/rotom.shtml for full details.
it changes the form of rotom but im not sure where and how
when u get the secret key from the mystery gift u go to the galatic HQ in eterna and go to the wall by the big box on the right and use the key their and a door will appear
use the itemfinder app behind the hotel entrance
You have to obtain the secret key and head over to the first floor of Team Galactics HQ. It is by the TV and the machine equipment by the reciptionist. Just push "a" and you will have the option to use the secret key. As for obtaining the secret key there are only two ways I know of: 1) wait for a Pokemon event in your area to receive the secret ket 2) purchase an action replay for the ds and find te code for the secret key online