windows xp professional product key not working?

[ojricardo]

hey guys, i've recently reformatted my harddrive so obviously i had to reinstall windows, all is fine until i am asked for the product key, i enter my key found on the sticker (i've reformatted the HDD twice with this key with no trouble...and with the same disk) and it says its not valid.....what could be the problem?!
help would be much appreciated,

cheers

[DallasDon]

My expereicne has been it's usually a typo on my part.

Watch those 8's and B's, Y's and V's, G's and 6's, etc. and try again