file corruption after a virus

I formatted and reinstalled Win 2000, Norton antivirus, and Office 2000. Fine, everything works, but when I tried to access some Word files, I got a message saying I needed to reinstall, so I put the Office 2000 disk in but got an error message, Windows installer error 1603. It was looking for the file Data1.msi, which is on the disk. I then got a Office 2000 Professional error “Internal error 2755.” Does anyone know what that means?