b.Sign into the store with the same ID you used when purchasing AutoCollage.
c.Near the bottom of the page there are a few rows of links. Click on the "Account" link.
d.You will see a page entitled "Microsoft Store Account - Purchase History." The date and time of your order of AutoCollage should be listed. In the right side of this entry,
under "Items:", you should see Microsoft Research AutoCollage 2008, along with a line which says "License:" and shows your product key.
If you are sure you are typing in the right key and it still doesn't work you can get help from the Microsoft Store support team, their contact information is towards the buttom of the page