I think that this might by the Product ID and that Elaine wants the Product
Key which comes on the CD case which, infuriatingly, is often a paper one if
it came with your PC. It is amazingly easy for an inexperienced user to put
the CD into a hard case and discard the envelope, little thinking that the
sticker on it will be needed to make his very expensive piece of software
function if he a crash.
There is a discussion of the subject here.
http://opensourcerules.info/oem_key.html
Look for the words Lost Office Product Key online - there are utilities
available some free and some low cost but I don't know which, if any, work
with Office 2007.
Evi