Check recent records from the DPMRA source in the Application Event Log on %ServerName; to find out why the agent failed ...

1) Check recent records from the DPMRA source in the Application Event Log on %ServerName; to find out why the agent failed to respond.
2) Make sure that the DPM server is remotely accessible from %ServerName;.
3) If a firewall is enabled on the DPM server, make sure that it is not blocking requests from %ServerName;.
4) Restart the DPM Replication Agent service on %ServerName;. If the service fails to start, re-install the protection agent.