In some situations, errors encountered by Microsoft Office on Windows can only be resolved by either a repair or reinstall. In most instances, the "Online Repair" option will resolve issues with malfunctioning Microsoft Office products; per Microsoft Documentation: "The faster Quick Repair option is also available, but it only detects and then replaces corrupted files." To complete the Online Repair process, you'll need to have administrative access to the computer and an active Internet connection.
To repair your Microsoft Office installation:
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Open Settings on your computer.
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Select Apps.

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Select Installed apps for list of installed applications.

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Scroll down in the app list until you see the installed version of Microsoft 365 apps for enterprise.
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Click on the three dots to the right then click Modify.

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Select Online Repair.
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Click Repair.

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Click Repair to confirm you'd like to start the process.

The online repair may take some time to complete and is very similar to the installation process. Once complete, restart the computer to see if your issues with Microsoft Office have been resolved. If you're still having issues after running the online repair, the next step would be to entirely uninstall Microsoft Office and reinstall it.