Fix for Windows 2008/2008 R2 High CPU during Windows Updates


On March 13th, 2018, UCF IT noticed dozens of Windows 2008 and 2008 R2 servers at 100% CPU utilization. After opening a Microsoft support case, the root cause was deemed to be a Windows Update process issue. We are continuing to work with Microsoft to find a permanent fix.

Perform the following workaround steps on the affected server to resolve the issue.

  1. (Optional step - only perform if below steps do not work as it can cause a system crash)
    Terminate the svchost process that's at 100% CPU and the TrustedInstaller process (if there is one)
  2. Stop the wuauserv service
  3. Go into the registry and delete the SusClientId and SusClientIdValidation values in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate
  4. Start the wuauserv service again and immediately run the command "wuauclt.exe /resetauthorization /detectnow"