windows 8.1 pro with media center upgrade caused office 2013 to require activation code

one of our users updated their windows 8 to 8.1 pro with media center and immediately afterwards, she tried opening excel and it required her to activate office 2013 again so now she doesnt know keycode but why would this happen?
Tried running system restore but her only restore point is the same day this happened so no good.  Any suggestions?
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Please call Microsoft Office 2013 Activation phone number for help.
This is a bug. Ask Microsoft (although it won't help). Phone reactivation will succeed after talking to someone at least.
Download and install Belarc advisor:

It will give you a comprehensive report including the product keys/serial numbers of virtually every program installed.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
Ultimate Tool Kit for Technology Solution Provider

Broken down into practical pointers and step-by-step instructions, the IT Service Excellence Tool Kit delivers expert advice for technology solution providers. Get your free copy now.

dankyle67Author Commented:
I actually called microsoft and they said the product key showed up as never being activated which is strange since they user has been using the office suite for 8 months until this happened.  I had the user contact microsoft activation support and they were able to have her download the office 2013 for home and business since the one she had was the professional version which is also strange since the product key we had was for home and business so im assuming that whoever did the install for her had probably installed a trial version of office 2013 pro but the version that came with the laptop was the home and business version since thats what her product keycode came up as when microsoft searched for it on their database.  Thanks for the info since the Belcarc will help for future issues when we need to locate product keys/serial numbers.
Great.  :-)

Note: Belarc will not give Office 2013 key (or the correct key). :-(
dankyle67Author Commented:
Ok thanks for the clarification.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Windows 8

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.