I upgraded to Office 2016 when it was released but still receive updates for Office 2013. The old version is not listed among the installed programs nor is anything relating to it in the Office installation folder. I've tried many uninstallers including MS own Office remover in vain. Finally I checked the registry and found several Office entries, both 2013 and 2016, marked "uninstallable". This when apparently no Office program was installed at all. Can I just delete these "uninstallable" keys, and then run MS Office remover? Would it not cause any harm or instability in my system? If not, how to get rid of everything related to any Office version and reinstall the latest on blank? Thanks a lot.