Installing the educational version Photoshop CS6 Extended

Hi

I have the CD version of Photoshop CS6 (educational version).   I have received my verificaton serial number.

However when I try to install it it only asks for a 6 digit number?    Which I dont have.    I have tried logging onto the education site but I am still asked for a 6 digit number.

Please can you advise?

Thank you