Using Three Monitors with Remote Desktop When You Have Four

By default, Windows Remote Desktop makes it easy to use either a single monitor or all of your monitors. However, if you have four monitors and want to use only three of them for Remote Desktop (leaving one for local applications), you can configure an RDP connection to do exactly that.

Step 1: Find Your Monitor IDs

First, you need to identify which monitors are available to Remote Desktop and their IDs. Open Command Prompt on your local PC and run:

mstsc /l

This displays the monitors that Remote Desktop can see, together with their IDs and positions. For example:

0: 1920 x 1080; (0, 0, 1919, 1079)
1: 1920 x 1080; (1920, 0, 3839, 1079)
2: 1920 x 1080; (3840, 0, 5759, 1079)
8: 1920 x 1080; (5760, 0, 7679, 1079)

In this example, the physical monitor arrangement from left to right is: Monitor 0 | Monitor 1 | Monitor 2 | Monitor 8

Note: Monitor IDs do not necessarily run sequentially. Here, the fourth monitor has ID 8 rather than 3.

Step 2: Save Your RDP Connection

Open Remote Desktop Connection by running:

mstsc

Configure the connection normally, including the computer name and any other required settings. Then click:

Show Options -> General -> Save As

Save the connection as an .rdp file somewhere convenient, such as your Desktop or Documents folder.

Step 3: Edit the RDP File

Right-click the saved .rdp file and open it with Notepad. Make sure it contains:

use multimon:i:1

Then add a selectedmonitors setting containing the IDs of the three monitors you want to use.

Step 4: Choose Your Monitor Configuration

To use the left-hand three monitors: For monitors 0, 1, and 2, add:

use multimon:i:1
selectedmonitors:s:0,1,2

Remote Desktop will use: Monitor 0 | Monitor 1 | Monitor 2, leaving Monitor 8 available for your local applications.

To use the right-hand three monitors: For monitors 1, 2, and 8, add:

use multimon:i:1
selectedmonitors:s:1,2,8

Remote Desktop will use: Monitor 1 | Monitor 2 | Monitor 8, leaving Monitor 0 available for your local applications.

Important: Monitor Layout

The selected monitors need to form a suitable contiguous arrangement. With four identical monitors arranged horizontally:

0 | 1 | 2 | 8

Either of these selections works naturally:

0,1,2   (left three)
or
1,2,8   (right three)

Step 5: Save and Connect

Save the .rdp file in Notepad. From now on, start the Remote Desktop session by double-clicking this .rdp file rather than creating a new connection through mstsc.

The Remote Desktop session should then span only the three selected monitors, leaving the fourth monitor available for local applications.

Quick Reference

List available monitor IDs:
mstsc /l

Enable multiple monitors:
use multimon:i:1

Use the left three monitors:
selectedmonitors:s:0,1,2

Use the right three monitors:
selectedmonitors:s:1,2,8