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CPU load, Disk Free, Memory sensors not working




a week back, I noticed that one of my VMs stopped showing values for CPU Load, Disk Free and Memory + Uptime and turned red for down.

Fallback to WMI is claiming the is Unable to access the desired computer or service and to check for permissions.

I did that, I also used WMI tester from your websites and I have results from the tool, but not from web monitor nor from Enterprise console.

Also, I noticed that I cant trigger manual check for the sensor.

Any idea what this might be? Thank you.

cpu-load memory wmi

Created on Apr 10, 2018 7:46:06 AM

3 Replies



Dear MrInfro,

in those cases it would be helpful to check if the sensors work again of the probe service is stopped and restarted. This creates fresh WMI connections.

If the WMI connection issues appear again and again, the probe performance should be checked. Please also make sure to use an up-to-date PRTG version.

Created on Apr 10, 2018 12:44:19 PM by  Arne Seifert [Paessler Support]



Hello Arne,

I restarted the probe service and even the target computer.

Also I am using latest PRTG installation and the probe health is at 100 percent.

What is completely confusing me, that when I run WMI tester from the probe computer, it will get results from the target computer, but for some reason PRTG server wont.

I am using same credentials for WMI tester and for PRTG.

Created on Apr 11, 2018 1:46:39 PM



Dear MrInfro,

in this case, the analysis can be more complex. As screenshots and log files are required, this case would better be handled as a support case. If your PRTG is connected to the internet, please use the web interface to contact the support, and attach the support bundle (which is the default option there.)

We will probably then ask you for further information, but said support bundle is a good start for analysis. If there are issues with contacting us through the PRTG web interface, write an email to [email protected]

You can mention me (Arne) being on that case.

Created on Apr 11, 2018 5:05:37 PM by  Arne Seifert [Paessler Support]

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.