Terminal Server Registry Keys of Interest

HKEY_LOCAL_MACHINE

SOFTWARE\Microsoft\Windows NT\CurrentVersion\Terminal Server\Install\Change User Option

SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon

SYSTEM\CurrentControlSet\Control\Terminal Server

SYSTEM\CurrentControlSet\Control\Terminal Server\WinStations\RDP-Tcp

SYSTEM\CurrentControlSet\Control\Windows

SYSTEM\CurrentControlSet\Services\Tcpip\Parameters

SYSTEM\CurrentControlSet\Services\TermService\Parameters