I am trying to set up wake-on-lan for my office desktop (Windows 7 Enterprise). I want it to sleep when I am not there, unless I wake it up remotely and use it in a remote desktop session. Things initially work ok out of the box (no changes in BIOS or network adapter): if the desktop sleeps, my RDP session wakes it up (it beeps), then I can enter my password. However at this moment the RDP session stays stuck on the welcome screen, forever:

This happens both for reconnecting to existing sessions or for logging in as a new session. Things only get unstuck and the RDP session wakes up completely when I move the mouse (the desktop's own physical mouse , not the mouse on the remote client - I am testing this from a laptop in the same room, so I have physical access to the desktop). Any idea what I should do to make the desktop wake up completely even when I have no physical access to it?