It may be that the previously installed office was not completely uninstalled. Clean up the original office with MicrosoftFixit, a tool specially designed for uninstalling office, or use Windows Install Clean, a self-produced uninstallation software produced by Microsoft, to forcibly uninstall the originally installed office, delete all folders and files with office on drive C, and then clean up the garbage and book list, so that it should be possible to reinstall.

★★★★★★★ Delete the backup files left by the update (you can also use security guards or optimization software to slim down and delete the system).

If not, ※:

Run regedit to open and find HKEY _ Local _ Machine \ Software \ Microsoft \ Windows.

Nt \ currentversion \ image file execution options directory, right-click menu permission command: Look, if you only check Read, check Full Control Permission, then click Add, enter your current system user name, click OK, and then check Full Control Permission. Give it a try.