Why do you need an unattended RDP session?
There has to be a better way than RDP if you need to gather information from a remote system unattended. Maybe we can assist with a better method if you share what your trying to do. Additionally VNC would work better I am thinking if you need a remote access session. VNC would work out better if the connection was interrupted to where the connection can be remade and the desktop etc would still be up and running with whatever you have going on. A RDP session dropping out isnt as graceful as VNC.
Additionally looking at your past posts here... how do you have RDP access to Server 2008 yet you dont have Admin Access to go in and make necessary changes in Server 2008?
Hopefully you didnt find someones open RDP on port 3389 and a weak password to get in etc. It just sounds really strange is all I'm saying. Not saying you are, but of everything i have seen in past posts it appears that you might have access to a system that maybe you shouldnt have access to. So hoping you can disprove all the flags that are popping up that to me I'm very cautious to assist with this because of how odd this is. Analogy to what I see = A shopping cart with everything to make a bomb draws attention until it can be disproved that its being used for a non-destructive application such as just needing to fertilize the farm, and the plumbing supplies are for the water system for the animals etc.