Having read a few threads about intermittent and strange problem monitoring with WMI I have found the following:
I use local accounts on my windows machines for monitoring. If I leave the Domain/Computer field blank in the Windows Credentials section then Perf. Counters work OK but I have issues with WMI only sensors. If I put Localhost or the machine name then WMI only sensors work fine but Perf. Counters fail.
Is there a way I can make both types of sensor live happily on the same device?