System center Management health Service unloaded System Rule(s)

Hello,

I am getting an alert in my SCOM 2012 for most of my Systems.i have done many things to solve this issue but bear no fruit  :(.

The System Center Management Health Service 123-31234  running on host xxx-xxxx.Root.net and serving management group with id {0407FB6F-896A-7389-EA01-D60C72ABBD5A} is not healthy. Some system rules failed to load.

I restarted the Service System center Management Service,also delete the folder health service State folder to clear the cache,but still the problem is there.i get the above alert.

Please can someone helpe here????????

Thank You!