Exchange 2007 Management Packs do not automatically monitor Exchange servers
The folks over on the System Center Operations Manager product team blog just posted a great article on how by default, the Microsoft Exchange 2007 Management Packs for Operations Manager 2007 will not automatically start monitoring of any Exchange 2007 Servers even if you have imported the Management Pack. This means that the servers won’t automatically show up in the Exchange views in the monitoring section of the console.
Never fear though, because if this is something you want to do then they have all the steps necessary to get this working:
J.C. Hornbeck | System Center Knowledge Engineer