Windows 7: win 7 hp to win prof upgrade

1st post. Hi i've purchased an asus k53e notebook for my son which has win 7hp installed. i've also got win 7 prof which i downloaded and paid for with authorized key. My question is this, can i use the anytime upgrade facility and use my genuine prof key instead of using the dvd with the downloaded prof 7 which i burned?

ps. I'm not too proficient so answers should be kept simple please...dooooooooooh

Many thanks,

Sean

YES.

No install files needed.
Only the Upgrade key is need.
Anytime upgrade only adds-on the Programs & Features from version to version.
Windows Anytime Upgrade - How to



Did you make the OEM manufacturer's Recovery Disks?

Thanks fellas.
Yes i've already made recovery discs of the factory installed win 7 hp.
When i use the anytime upgrade will any other factory installed apps remain on the system or will they be deleted?
Thanks once again for the very quick responses
TT

Nothing will change at all except a few expensive features will be unlocked and your version will read Pro instead of Premium.

Nevertheless back up an image and your files as a matter of course with any upgrade or reinstall against the extremely rare possibility of failure. You also want to save an HPrem image so you have an easy path back.

Thanks a lot

More help please.
i've tried to use the anytime upgrade function. It allows me to enter my key (which i received after paying for the student upgrade download <burn to disc>,
but eventually leads to the message "ENTER A DIFFERENT UPGRADE KEY. the key you entered does not work with anytime upgrade"