word err message you are dangerously low

Hi,
I have a clients pc that has word as part of works. They also have other components as part of office installed. The pc came in for system optimization and tune up. As part of this I ran virus scan, it had a virus and it was removed. Word has been uninstalled and reinstalled but not office. Whenever the client goes to use word this error message comes up. You are dangerously low on resources would you like to close this application, if you say yes, it does the same thing over and over. Thevirus was removed so I am not sure what is going on.