Reinstalling Office is a bigger step than repairing it, but it can clear stubborn problems or set up Office cleanly on a new computer. Your Word, Excel, and PowerPoint files are separate from the apps, so uninstalling Office does not delete normal documents.
Does this affect you?
Use this for Microsoft 365 subscriptions and Office 2021 or 2019 one-time purchases on Windows or Mac when repair did not help, the computer was reset, or you need a fresh installation.
Uninstall and reinstall on Windows
Confirm your license account before removing anything.
- Go to office.com or account.microsoft.com/services and sign in to confirm which Microsoft account owns the Office license.
- If Outlook uses a local PST file, locate and back it up before uninstalling. Cloud Exchange, Microsoft 365, and IMAP mail usually re-downloads.
- Open Apps and features from Windows search.
- Find Microsoft 365 or Microsoft Office and choose Uninstall.
- Restart the computer after removal finishes.
- Return to office.com, sign in with the licensed account, and choose Install Office.
- Run the downloaded installer.
- Open any Office app and sign in to activate.
Uninstall and reinstall on Mac
Office for Mac is removed by deleting the apps, with optional cleanup for troubleshooting.
- Quit all Office apps.
- Open Finder > Applications.
- Drag Word, Excel, PowerPoint, Outlook, and other Office apps to the Trash.
- For deeper cleanup, use Command+Shift+G and inspect ~/Library/Containers and ~/Library/Group Containers for Microsoft Office support folders if Microsoft instructions call for removal.
- Empty the Trash.
- Sign in at office.com and download the Mac installer package.
- Run the .pkg installer and follow the prompts.
- Open an Office app and sign in to activate.
More control
What stays safe
Documents stored on the computer, OneDrive files, and cloud mailbox data are not removed just because the Office apps are uninstalled.
What may need rebuilding
Custom Quick Access Toolbar settings, some add-ins, local templates, AutoCorrect customizations, and local Outlook PST data may need backup or reconfiguration.
Device limits
Microsoft 365 plans can have installation or sign-in limits. Check Apps & Devices in your Microsoft account if activation fails on a new computer.
If a reinstall does not help
If Office still fails immediately after a clean reinstall with no add-ins loaded, test Windows or macOS account health, disk errors, and profile corruption rather than reinstalling Office repeatedly.
Sources
- Microsoft Support – Uninstall Office (2025)
- Microsoft Support – Download and install or reinstall Office (2025)
- Microsoft Support – Uninstall Office for Mac (2024)