I believe you're missing some very important details:
* What is your operating system?
* What version of Microsoft Works?
* Is it an OEM or retail version?
* Where did you purchase it? (Name the store/site.)
* The software is all on the CD, so what (and why) did you download?
* Had you used that product key on another computer before?
P.S. I believe you mean you performed a system recovery, which formatted your system and reset it to its original factory condition.
Cause i did that thing called something i forgot. but it reset your computer to the factory settings. but before i did that i had microsoft works on my computer. After i did that system thing?? it was gone. So i put the microsoft works disc in my computer and then it downloaded but it ask me for the product key, i put in the product key and then it said it already been used. So how do i get it to work. I hope i didnt waste my 80+ dollars.