Workstation Monitoring stops after a client reboot

Workstation Monitoring stops after a client reboot

Morning,
 
I am trying out the OpManager software and have tried to monitor a workstation to see what its like, I have setup the performance counters CPU and Memory, connected via wmi (winxp) using my admin credentials, it works all day then when the machine is powered down and back up again the performance monitors stop working. I have tried the Test Credentials which passes, and the Test Performance Monitors which Fail, i can remove the monitors and add them again and it starts working.
 
I'm assuming i am not doing something correctly? Monitoring Servers wouldn't be a problem as they hardly powerdown but Workstations do all the time and there are a few that i need to monitor without having to add and remove the monitor on a daily basis. I've also noticed that when removing them and adding them again i lose all the statistics for previous days.
 
Any help would be greatly appreciated

                New to ADSelfService Plus?