When Remote Controlling to a PC where the user has connected via RDP you only see the login screen.
Is it possible to see the user's RDP session?
This was possible with Windows XP, but is an issue with the Session 0 Isolation on Services and Drivers in Windows Vista and newer Operating Systems brought in by Microsoft in their new OS’s. This prevents the Remote Control Viewer accessing these other sessions that are initiated when RDP connections occur as the LANDesk Remote Control Service runs under session 0.
Previously it was possible for Session 0 to access other Session's hence the reason it worked for Windows XP.
A workaround could be to have the user browse to the LDClient folder and launch the issuser.exe. This will allow the remote control session to run under the logged on user, which should allow Remote Control to the RDP session that the user has established.