When i try to access a VirtualBox Windows 2003 server guest hosted in a Google Compute Engine Debian Wheezly by any RDP, the logon screen appears and when i press Ctrl-Alt-Del task manager came up.
Well i found a realy nice solution. If you quickly press 5 times left shift StickyKeys will appear, then press OK and StickyKey will activate. Then you press the Ctrl Alt Del sequencially, not at the same time.