Migration assistant did not copy MS office activation info

I just upgraded from MacBook Air 2011 (Mavericks) to a new 2015 model (Yosemite). When I first turned the laptop on, I followed instructions using Migration Assistant - Mac to Mac Transfer - all options checked settings/apps/documents/data. So everything appeared to transfer except now MS Office is asking for serial numbers and activation codes. When I entered them it say is not a legitimate copy even thought I bought and paid for it and have been using it for 4 years on my other Mac without problems.

Is there another file that i need to move/transfer manually from my old Mac for it to recognize my license? Or any suggestions on a work around? I really don't want to buy another copy, and I plan on removing it from my old Mac by doing a full restore to wipe out my personal data before I sell it.

any help is appreciated