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Blanking the host screen during remote control

Protect sensitive data by blanking the host display during a remote control session. This is particularly useful for unattended remote computers to prevent others from entering data or viewing the monitor while you are remotely accessing it from another location. NoMachine's remote screen locking feature is designed to address this need.

How to enable screen blanking

This tutorial provides the steps to take to blank the screen of the computer you will be remotely accessing. It also assumes that you have administrator rights on that machine.

  • First install NoMachine on the computer or device you are connecting from and the PC or Mac you want to access. Consult the Getting Started Guide for details on how to do this.
  • Connect via NoMachine to the computer you want to access.
  • To lock the remote screen, first click on !M icon ("NoMachine Monitor") in your computer's application tray and select 'Show the service status'.

Select 'Show the Service status' in the NoMachine Monitor
Fig. 1 – Select 'Show the service status' in the Monitor

  • In the NoMachine Service Status panel click 'Server preferences' (Fig. 2).

Go to NoMachine Service Status and select Server preferences
Fig. 2 – NoMachine Service Status > Server preferences

  • Select the 'Security' tab and make sure the box is checked for 'Lock the physical screen when somebody connects' (Fig. 3).You can turn this feature on or off at any time. By default, it is disabled. You will need to provide the administrator's username and password in order to enable it or disable it.

To blank the screen on the remote NoMachine computer, check the box ‘Lock the physical screen when somebody connects'
Fig. 3 – Check the box 'Lock the physical screen when somebody connects'

Locking keyboard and mouse input

  • Turning it on also locks the host keyboard and mouse to prevent anyone sitting at the host machine from entering input data during a remote control session.
  • Anyone at the host device sees a blank screen on the physical monitor while the remote session is active.
  • That's it! Once you're done, upon disconnecting the screen will become visible again.