Azure AD Connect MonitoringAgent High CPU – Server 2016

So… I’m running an AD on an Intel NUC, and after a recent set of updates the NUC started to sound like a hairdryer!
 The ESXi Host was reporting some pretty fantastic CPU numbers (considering there’s not a lot of workloads on this yet, 3 VMs doing not a lot).

When having a look at the VM, I see most of the CPU being taken up by ‘Microsoft.Online.Reporting.Monitoring.Agent.Startup’. This is a component of Azure AD Connect, which I’m using to sync user accounts into Office 365 for my Lab.

Some time later and a bit of Google-Fu, I found this on MSDN. The initial comments mentioned that KB4054566 was to blame, but searching for the update it was not present on my system.
Some of the other suggestions mentioned:
  • Server 2008R2 “Microsoft .NET Framework 4.7.2”
  • Server 2012 = KB4054542
  • Server 2012R2 = KB4054566
  • Server 2016 = KB4054590

Another potential. However: AC58268A-EB8C-4006-AC1E-80F52F2297BC.png

Scrolling some more,  PieterPretorius came up with the following discovery. KB4338814!! This one had been installed the day I did the updates, and promptly uninstalled it. Head to Control Panel, Programs and Feature and click “View installed Updates” and find KB4338814.   FC22E1CF-5078-4AEA-ACED-ED58E49DB004 This took a little time to remove, and after a reboot the NUC had settled down back to near silent! I’ll be writing another post about keeping an Intel NUC NUC7i7DNHE quiet, as the default Fan settings are a bit… noisy.  Follow Up: Keeping KB4338814 at bay.  The next day I ran some more updates on the server and noticed that KB4338814 was coming back again! I had not tried to block updates on Server 2016 yet so had a look into it, as the usual methods I’d used in the past weren’t present. Head to: and download the wushowhide.diagcab file and run it.



All done. In my case, the update was already installing when I blocked it. I had to restart the server to finsh installing it, then remove it agian, and restart…. I’m very thankful this is in a Lab and not a production system!
Many thanks to for the information on how to hide Updates in Windows 10.

2 Replies to “Azure AD Connect MonitoringAgent High CPU – Server 2016”

  1. his is how I limited Microsoft.Online.Reporting.MonitoringAgent.Startup from eating all the CPUs
    Task Manager and right click on the Microsoft.Online.Reporting.MonitoringAgent.Startup process.
    Select “Go to details”
    Right click on Microsoft.Identity.Health.AadSync.MonitoringAgent.Startup.exe (should be the pre-selected row)
    Click set affinity, and uncheck “all Processors”
    Select CPU 0
    Your CPU usage will drop immediately (mine dropped to 32%)

    I can’t tell you if this is a good idea or not, nor do I know what complications or adverse affects in restricting it to CPU 0. So far I haven’t had any further issues. Restarting may revert the setting (not sure).
    Hopefully Microsoft will release a update soon.

Leave a Reply

Your email address will not be published. Required fields are marked *