My Windows sensors do not work when using direct performance counter access. What can I do?

This article applies to PRTG Network Monitor 19 or later

Error messages when using WMI (Windows) sensors with a hybrid approach

Some WMI (Windows) sensors can use a hybrid approach to query values from your Windows machines. When this option is set, they try to directly access performance counters. If the access request fails, they try to use WMI for the connection. This makes monitoring more robust and eases the load on both the monitoring and the target systems.

Up to PRTG 17.1.30, the default option for these WMI (Windows) sensors was Performance Counters and fallback to WMI in case the first attempt failed. As of PRTG 17.1.30, the default option is WMI only because of major improvements to the underlying WMI engine in PRTG.

This option is set in the PRTG device (!) on which you create the WMI (Windows) sensor. You can change it in the Windows Compatibility Options section of the device settings.

Note: You can set this option at group level as well. Set it for the Root group, for example, so that it is valid for your entire device tree.

If the hybrid approach of WMI (Windows) sensors does not work

If your WMI (Windows) sensors do not work using the hybrid approach, there is likely a problem with directly accessing the performance counters, and for some reason, the fallback does not work either.

In this case, we recommend that you use the WMI only option (default as of PRTG 17.1.30). This option is set in the PRTG device (!) the Windows sensor is created on. You can change it in the Windows Compatibility Options section of the device settings.

Note: You can set this option on group level as well. Set it for the Root group, for example, so that it is valid for your entire device tree.

Reasons for unsuccessful access to performance counters

If the access request to the performance counters fails, check or try the following:

• The machine running the PRTG probe (either the local probe or a remote probe) must run on Windows Server 2008 R2 or later.
• The Remote Registry Windows service must be running on the same machine.
• The machine running the PRTG probe and the target machine must be part of the same Windows domain.
• Check if the Windows credentials that you entered in PRTG are correct.
• If you use a local user to monitor a target machine that is not part of a domain: This user account has to exist on both the system with the PRTG probe and the target system, that means, with the same username and password. In the device settings in PRTG, under Credentials for Windows Systems, leave the Domain or Computer Name field empty.
• Try to get access with the credentials of a Windows Domain Administrator account.
• Some counters may be missing or may not contain counter data, or the performance counter libraries may become corrupted. This behavior can occur if certain extensible counters corrupt the registry, or if WMI-based programs modify the registry. In this case, you must rebuild the performance counter libraries. For details, refer to the Microsoft article How to manually rebuild Performance Counters for Windows Server 2008 64bit or Windows Server 2008 R2 systems.
• Try to restart the target and the PRTG probe service of the probe(s) monitoring the target(s).

Important error codes

You can find the whole list of possible performance counter errors in the Microsoft article Performance Data Helper Error Codes.

More

• How can I find out the names of available performance counters?

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.