If not Done, Please follow the Steps below:
1. Uninstall Complete MS Office in the system with the folders available in Program file / Program files(x86).
2. Remove registry keys created by the MSI installation of Office by deleting the registry keys -

- Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office

- Computer\HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office

- Computer\HKEY_CLASSES_ROOT\TypeLib\{00020813-0000-0000-C000-000000000046}\------
3. Restart the system.
4. Now Install MS Office.