Forum Discussion
MS Defender - Installation Error version 101.25072 on macOS
Dear experts,
The latest version of MS Defender can't be installed. I'm getting an error message since release date (5th Aug). I have tested to restart the computer, tested with different networks, same issue 🙁
FYI...MS has this posted on their service health status page. They have a fix in the works but sounds like it will be a "side channel" upgrade of some kind. I'm betting we'll be having to push a shell script via MDM that will end up doing a "rip and replace" of sorts.
https://admin.cloud.microsoft/?#/servicehealth/:/alerts/DZ1144032
UPDATE: Microsoft has published the fix. As near as I can tell, it involves pushing out an MDM profile to enable a tamper protection exclusion only for a special "upgrade helper" package Microsoft has provided. You then push out the pkg which sets tamper protection to audit mode, upgrades Defender, then turns tamper protection back on. Instructions and the helper package are found in the below link, which was published in the service health alert linked above.
https://github.com/microsoft/mdatp-xplat/tree/master/macos/upgrade_from_2506_helper
22 Replies
Same for me on M3 running 15.6.1
Getting the same error. On intel running Macos 15.6.1 (24G90)
First check /Library/Logs/Microsoft/mdatp/install.log on your device. Hopefully you'll find more detailed information in why the installation fails.
You can also check if Microsoft Defender and MDE Security Extension has full disk access on your MAC. If not, change to full access and don't forget to restart your MAC. After reboot, try the install again.+1 Same error on various M Mac models.
+1
Getting the same error. On intel running Macos 15.6.1 (24G90)
Same for me.
Experiencing the same thing here.
Hi Yasin,
Thanks for sharing this—I've seen similar issues with Microsoft Defender updates on macOS, especially when AutoUpdate gets stuck or misaligned with system permissions.
Here are a few things you might try:
- Clear the AutoUpdate cache (look under ~/Library/Application Support/Microsoft/MAU).
- Try a manual install: download the latest Defender build directly from Microsoft instead of using AutoUpdate.
- Check permissions: make sure Defender and AutoUpdate have full disk access under System Settings → Privacy & Security.
- If your device is managed with Intune, review update policies that might be interfering.
If none of those help, it’s worth opening a Microsoft Support case—especially since it’s persisted across networks and restarts.
Hope that helps, and thanks again for raising it!
