SCOM windows 7 reporting issue

Hi Guys,

I am facing a problem with reporting of windows 7 machine. I am monitoring  windows 7 machines with scom 2007 r2. But on some of the machines, when i am running the performance reports(cpu,memory) its coming blank.This issue is only on few machines. My performance collection rules are also enabled.

Plz help

Thanks,

Ashish