How to fix “Invalid Class” error when monitoring a process

Posted on October 18th, 2018

I recently had a customer have an error indicating “Invalid Class” when monitoring a process. This was a resource that worked perfectly until now. This is a known issue when Windows performance counters are unavailable or disabled. The primary culprit is a registry key that explicitly disables them. To fix this error, open HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\PerfProc\Performance\ in regedit. Check for “Disable Performance Counters” value in the right pane. If it’s there and set to 1, that’s the problem. Set it to 0 and reboot the computer. This should be done on both the Overseer computer and the computer being monitored. This fixed my customer issue, and it can fix yours. If it doesn’t, please contact us so we can work through a solution with you.