★★★★ It may be that the previously installed office was not completely uninstalled. Use MicrosoftFixit, a special uninstall tool for office, to clean up the original office, or use Windows Install Clean, a self-produced uninstall 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 lists.
★★★★ 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 360 and QQ Computer Manager are installed, please uninstall or shut it down first.
Office uninstall tool
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Then refer to:
Microsoft help and support
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