SCOM Agent became grey out after deployment Agent and Windows O.S not monitored.
To fix this issue, Verify from following:
- Firewall Port 5723 and ports of DC Authentication are open.
- Antivirus allow SCOM Agent, monitoring Files and ports.
- Action Account isn’t lock down/out.
- DNS Resolution from MS to Agent and ViceVersa.
- Connectivity available between Agent and MS.
- Check this KB 2288515.