Office 2007 Not activating

[baseball7]

I rebuilt my system a few months ago, and office was working just fine. Until today when my sister went to use Word, it said that i needed to activate the product over the phone or online.
I try Online: it says i have already used all of my downloads for this product. But since i rebuilt the system, i really havent.
I try over the phone: it closes the window and im just looking and word, not being able to do anything because the product isnt activated, so Word is locked.

I know there is an obvious fix somewhere, but ive tried a few and nothing has worked.
Any ideas?

Thanks

 

[tremmor]

call microsoft support. Ive done it and worked. Usually a upgrade of motherboard or change video card will require this call. they always gave me a new key.

 

[baseball7]

is there a certain Number i have to call? or can i just call customer service?