Hi Paolo,
This forum is for System Center Essentials(SCE) related issues. For questions about System Center Operations Manager(SCOM), please use the following Forums, which would be the best resource in your scenario.
System Center Operations Manager Forums
http://social.technet.microsoft.com/Forums/en-US/category/systemcenteroperationsmanager
Thanks,
Yog Li -- Please remember to click “Mark as Answer” on the post that helps you, and to click “Unmark as Answer” if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.