Hi powerbook1701,
Good call on wanting to remove it — macOS has its own built-in security (XProtect, Gatekeeper, and MRT) so Microsoft Defender is unnecessary for most Mac users. Since you haven't opened or activated it yet, the removal should be clean. Here's how to do it properly:
- Remove the app: Open Finder, go to the Applications folder, find Microsoft Defender and drag it to the Trash. You may be prompted for your admin password.
- Remove leftover files: Microsoft Defender installs components outside the Applications folder. Open Terminal and run these commands one at a time:
sudo rm -rf /Library/Application\ Support/Microsoft/Defender
sudo rm -rf ~/Library/Application\ Support/Microsoft/Defender
sudo rm -rf ~/Library/Preferences/com.microsoft.wdav.plist
sudo rm -rf ~/Library/Caches/com.microsoft.wdav
- Check for system extensions: Go to System Settings > General > Login Items & Extensions. Look under Background Items and Extensions for anything related to Microsoft Defender. If you see any entries, toggle them off or remove them.
- Check for launch daemons/agents: In Terminal, run:
ls /Library/LaunchDaemons/ | grep -i microsoft
ls /Library/LaunchAgents/ | grep -i microsoft
ls ~/Library/LaunchAgents/ | grep -i microsoft
If any results mention Defender (not Office), remove them with:
sudo rm /Library/LaunchDaemons/com.microsoft.wdav.[filename].plist
Replace [filename] with the actual file name shown in the results.
- Empty the Trash and restart your Mac to make sure all background processes are cleared.
- Verify it's gone: After restart, open Activity Monitor and search for "Defender" or "wdav" — nothing should appear. Also check System Settings > General > Login Items & Extensions again to confirm no Defender entries remain.
Your lesson learned is a good one — Microsoft's Office installer bundles Defender by default unless you customize the installation. For future reference, if you ever need to reinstall Office, you can download the individual apps (Word, Excel, PowerPoint) separately from Microsoft's website instead of using the full suite installer.
Your Mac's built-in security is excellent on its own, especially on Apple Silicon with Tahoe — you won't miss Defender.
Hope this helps!
