We have had performance issues for a few weeks at night, all our Hyper-V Servers where performing like CRAP every night around 3 AM and for about 45 minutes.
After a long night of investigation with my colleague, we found out that Windows 2012 is running a maintenance job around 03:00 each day.

When we stopped it all began to run as normal. This caused overloading of the SAN SP and gave high disk queue on all servers attached to the SAN.
But, after we disabled the Scheduled Task “Regular Maintenance“, it got enabled Again after some hours.
To avoy this disable “Maintenance Configurator“, but this can´t be done from GUI
To disable Maintenance Configurator run this command on a server with PsExec Link :
psexec \\SERVERNAME -s schtasks /change /tn "\Microsoft\Windows\TaskScheduler\Maintenance Configurator" /DISABLE

Note that the next time you reboot the server, the scheduled task will be re-enabled.
Hi Yossi,
That`s not correct, if you got the task “Maintenance Configurator” disabled it will NOT re-enable after a reboot.
I just tested it on one of our servers.
Hey guys,
If you have a WSUS server, this can be done through group policy.
Under Configure Automatic Updates, there’s a checkbox called “Install during automatic maintenance”. REMOVE THE CHECKBOX!
Do you know how to disable the maintenance on a 2012 Core install?
Hi Sam,
I´m not sure, but the easiest will be to install psexec on another server and run the command from there.
Thanks Lars, In fact psexec is the only way it will work. When I tried to do it without I kept getting “access denied”. It only works using the psexec program.
If you run the command directly on the server without PsExec you will get “access denied”. Run it on the Core server without the \\SERVERNAME part of the script, then it will run it on the local machine with the system account 🙂
OK, I did this. Successfully disabled Maintenance Configurator.
…BUT … could not connect to the internet anymore. Windows said connection OK, could see shares on other PCs on my LAN, but both Firefox and IE would not load web pages.
Internet connection is of type:
ControlPanel->System->.. Workgroup=
ControlPanel->Network and Sharing->Ethernet ->… Private (current profile)
I tried ENABLING the Maintenance Configurator, no joy.
I restored the disc image I made (with Macrium) just before this, and everything OK again.
Any ideas?
Hi Alex,
Thats sounds strange, i have done this on 5+ servers without any problems.
Hi Lars Jørgensen
I’ve try to disable Maintenance Configurator on my server, but it did not work.
it says “PsExec could not start schtask on …” my server”.
ok i’ve done it. i forgot to type “s” on schtask.
Thanks
try this update
http://support2.microsoft.com/kb/2975719
works for our case, in our enviroment Automatic Maintenance consume all the ram 40 GB and then create a large page file while defrag all 8 drives on our file server cluster, this cause a time out on cluster health check and failover resources to other node.after install this update problem resolved.
hope this will help
hi, Lars Jorgensen
Why not use GPO with a starting at 3000 years ?
Go to Computer Configuration->Policies->Administrative Template->Windows Components->Maintenance Scheduler–> And change this option: Automatic Maintenance Activation Boundary. Enable it and change the year from 2000 to 3000
hope this will help
Hi Ludovic,
Thanks, i will test that 🙂
I tried doing it as described, cut and paste. I’m running it from the server in questions. Initially I tried it with with server name intact. It kept saying it couldn’t find the file, but it wouldn’t specify which file.
Then, realizing I don’t need the server name when running it locally, I removed that, and now it says:
Error establishing communication with PsExec service on “my server”:
The system cannot find the file specified.
I’m obviously doing something wrong, but I’m not clear what.
Did you add psexec to c:/windows/system32?
Hi All,
What does this maintenance job actually do in the background? It’s one thing disabling it but what processes and procedures is it running? Completely switching off a scheduled task seems like a heavy handed approach to an issue but if it works! More curious to see if you had to readdress this in another way or did the hosts degrade in performance over time?
Thanks
It is interesting that after over 4 years this is still an issue! we had similar issues on many servers running on SANs. and this actually fixed it! so thanks heaps for that. I also have Dave’s question, is this going to have side-effects down the track!