We have just started the process of virtualizing all our physical Servers. I have noticed some issues when trying to monitor them with NPM and I just wondered if anyone else has come across this and if they were able to resolve them.
I have noticed drives (C or D) going into 'unknown' states then back to normal regularly during the day.

I have also noticed the Physical Memory Resource or Virtual Memory resource showing 'unknown' even though when you click on it you see the collected data.
Any advice would be appreciated, thanks