Can I blank the screen of a remote computer while I'm connected to it?

From VNC Server 6.3.2, you can blank the screens of most Windows computers (up to and including Windows 10). This is equivalent to turning the monitor(s) attached to a remote computer off so people in the vicinity can't see what you're doing.

Note: You cannot blank the screens of remote Linux or Mac computers, and there are limitations for some Windows 8 and 10 computers, particularly laptops (see below).

How do I enable screen blanking?

Open VNC Server's Options > Privacy page and turn on Blank screen when users are connected.

Screen blanking is hardware-dependent for Windows 8 and 10, so we recommend you test these systems first to make sure screen blanking will be effective:

Note: Avoid any users connecting remotely while a blanking test is in progress as it can prematurely blank the screens.

What operating systems support screen blanking?

Currently the Windows operating system is supported. Screen blanking for Windows 8 onwards is hardware-dependent, hence the recommendation to test your screen first.

What screen hardware supports screen blanking?

For Windows 7 and earlier, most hardware should be supported.

For Windows 8 and 10, most desktop screens manufactured after 2011 should be supported, including major manufacturers such as Dell and Samsung. The screen must have an independent power button; all-in-one computers are unlikely to work.

Unfortunately, there is not as much support for laptop screens, which are also unlikely to work.

How long does screen blanking last?

For Windows 8 and 10, VNC Server attempts to make screen blanking last for as long as possible. Screen blanking ends if: 

• The blanked screen is powered on again.
• Screens are added or removed from the system.

What if I can’t get screen blanking to work for Windows 8 and 10?

Assuming that your screen was manufactured after 2011 and is not a laptop display, you can try the following:

• Remove any base stations, splitters or repeaters used to connect your screens.
• Update your graphic card driver software to the latest version.
• If there is an option on the screen’s setup menu called MCCS or DDC/CI, enable that option.

If I need to contact you about screen blanking, what information do you need?

We need the following information:

• A debug server log, after you have performed the screen blanking test.
• The manufacturer and model of the screens that failed to respond to screen blanking.
• How the screens are connected to your system (HDMI, VGA, DVI, and so on).
• The manufacturer and model of your graphics card.