Backup hyper-v using child partition

Hi,

I am using DPM 2012 SP1 to backup my hyper-v servers.

All my servers are backed up using child state. But only one server that is backed up using saved state. This server was off when I set up the backup for it for the first time, that is why it showed me as backing up using saved state. I thought that when the server will be online, it will back it up using child partition, but it did not.

I tried removing the agent, reboot, re-install the agent. But still no go, it doesn't give me the option to back up using child partition.

Any help please.

Thank you.

-Mehdi