Windows service monitors down after v7 upgrade

Hi, I wonder if you can help?

I have just upgraded opmanager from v6 to v7. The upgrade appeared to work ok, however since then, the majority of my windows service monitors ar showing that the service is down. This is occurring on all monitored devices, and the majority of services are reported as down. So far I have tried the following

Restart of server and opmanager services
Repaired database
Deleting and adding in services
Deleting all services from all servers, and adding in again

All of the above fail, but i'm certain WMI is ok as i am able to browse the monitored servers and discover the services, and the status ok when adding in new service monitors