Patch Installation Failure- "Error code - 50020"


You are getting the error code - 50020 when you try to install the following Windows updates to the endpoints.

  1. KB4493467
  2. KB4493446
  3. KB4493448
  4. KB4493472
  5. KB4493450
  6. KB4493451
  7. KB4496880
  8. KB4496879
  9. KB4496878
  10. KB4496877
  11. KB4493453
  12. KB4493443
  13. KB4493462
  14. KB4493460


The problem is due to the following reason.

  • You have Sophos Endpoint Security installed in your endpoints and you're trying to install the above mentioned updates.

Microsoft has acknowledged this in an official statement that "Microsoft and Sophos have identified an issue on devices with Sophos Endpoint Protection installed and managed by either Sophos Central or Sophos Enterprise Console (SEC) that may cause the system to freeze or hang upon restart after installing this update."


To resolve this issue, decline the mentioned Wndows updates to the endpoints. You can decline the updates from Patches > Missing Patches > (select the updates) > Mark as > 'Declined' and select the target computers for which the update has to be declined.

Reference link to the official KB document by Sophos:

If problem persists, contact support