A family of Microsoft word processing software products for creating web, email, and print documents.
Before #1 & #2, try #4 followed by a power off shut down. See if the issue continues when you start up again.
Also, has the Mac experienced any crashing while running Word? Specifically when is the error message triggered & what is the exact wording of the entire error message?
Is this the same Mac being transported from work to home?
Complete & accurate details are needed to resolve issues like this -- there are just too many variables that can factor into any given user's experience.