yes you can, i have before, its just this time i got a error, i've done both the upgrade and the other.
If i am guessing right, windows upgrade created a Shadow Copy on my pc and if my understanding of the words Shadow and Copy are right, it is quite indeed possible that windows created a back up on my HD but so it wont take space it made it where it will be there but not in the way; IE a shadow copy. If i can delete that and delete system files it might be able to upgrade, i will try this and hope it works.