How to Fix Windows Update Error 0x80073712 - Windows Defender Not Starting After Update-Fix Windows Update Error 0x80072efd: Connection Refused

Updated 2026-06-13 13:23:49security-tools
How to Fix Windows Update Error 0x80073712 - Windows Defender Not Starting After Update-Fix Windows Update Error 0x80072efd: Connection Refused
Before changing system settings, save your work and note the exact error text so you can compare results after each step.

Extra verification checklist

  • Restart the affected app after changing permissions or configuration files.
  • Test the same workflow in a clean browser profile or a temporary user account.
  • Compare the result on another network if the error may be connection related.