Hi everyone,

I have an WMI error code in our PRTG environment and I can't find a real solution on the web.

The Message shows:

"80041064: The user specified a username/password/authority on a local connection. The user must use a blank username/password and rely on default security.- Note: the OS version of the device could not be determined, WMI might not work reliably."

The thing is, that this happens only on one machine with the free disk and memory sensor. All other WMI sensors on the other machines are working correctly. The sensors worked well but suddenly both failed. The CPU load sensor is working the whole time.

Thanks for your feedback!


Article Comments

Hello tobiasnikola,
thank you for your KB-Post.

  • Which Windows version runs on the target System and on the PRTG Probe that is polling this device?

Did you review our general WMI troubleshooting guides?

Please also make sure that you're running the up-to-date stable PRTG Version for best results.


Best Regards,
Luciano Lingnau [Paessler Support]


Sep, 2016 - Permalink

Hi Luciano Lingnau,

thanks for your quick reply to my KB-Post. I have successfully fixed the WMI sensors for Free Disk and Memory. The rebuilt of the repository seems to be solution. I tried a lot of the command prompts and some reboots and now it is working again.

The system is a Windows Server 2008 SP2 64bit.

Best Regards, Tobias Nikola


Sep, 2016 - Permalink

Hi Luciano,

  • the good news first: the wmi sensors worked for about 2h
  • the bad news: they stopped working again Now I've disabled the windows authentication for this special server and the wmi sensors are working again. I hope this will be the final result.

Regards Tobias


Sep, 2016 - Permalink

Hello, I've the same problem. The OS versione is Windows 2008 R2 Standard SP1.

Thank you.

Best Regards, Rolando


Nov, 2016 - Permalink

Hello Rolando,

please review the following suggestions/links

And make sure that you're running the very latest available PRTG Version, which is currently 16.4.27.7141.


Nov, 2016 - Permalink