Q: Why are some servers monitored in Operations Manager grayed out?
A: A monitored server that is gray simply means that there's a communication problem between the server being monitored and the Operations Manager server. This is shown in the Management Server State view and the agent's Health Service Watcher class instance view.
To troubleshoot, there are two actions to take:
- Use Health Explorer for the server to examine possible problems.
- Look at the Operations Manager event logs on the problem server.
The Microsoft Support article gives more detail on the troubleshooting and is a great resource to use.