Quick guide to using a remote desktop with multiple monitors

Benefits of RDP 

RDP has been a game changer in terms of supporting clients remotely. Not only are flexible, hybrid arrangements the new normal, but we also have to support workers in multiple locations - the days of support being limited to the primary office are well and truly over. RDP allows MSPs to support remote clients, have hybrid work environments, or occupy multiple sites. Without remote access software, support techs would need to be onsite with customers to be able to troubleshoot, diagnose the fault, or make changes to end user devices.

If work needed to be done remotely, the technician would have to talk the user through the steps over the phone, which isn't ideal from an efficiency or experience perspective. RDP solves this problem making it easier to provide seamless remote support. As we all lead into working more efficiently after the pandemic, an essential requirement of remote support is being able to work with multiple monitors. Let's get started on the best support options.  

Do your prep work

First, if you're supporting a customer using older equipment, check that their estate supports the multiple monitor option. If you have Windows 7 systems, the OS version should be either Enterprise or Ultimate for multiple monitor support. For Windows 8.1, it should be Professional or Enterprise. Another thing to note is that Remote Desktop supports 16 monitors maximum with maximum resolutions of up to 4096 x 2048 per monitor. 

Using Remote Desktop to view multiple monitors

Ask the end user to go to their search bar or Quick Assist onto their main screen (if you can face the whole "let's just fire up Quick Assist" conversation*) and ask them to type in "Remote Desktop." This will give them the Remote Desktop Connect application, and once they click on it, they'll be prompted to enter the relevant details and can select display settings by clicking on the More Settings button. In the Display settings tab, make sure the use all my monitors for the remote session checkbox is selected as follows:

A pro tip at this point is to click back to the General tab, then select the Save As option so you can save the RDP settings as a template. This means that you won't have to keep re-entering credentials or toggle buttons when you want to access the machine in question from a remote PC.

Running RDP for multiple as a command

An alternative option for monitoring multiple screens is to use a command. The Remote Desktop connection tool that is built into Windows allows you to use multiple monitors for remote sessions. It's not enabled by default, so first press the Windows and R buttons, type CMD, and hit Enter. A command prompt will appear; you can pre-enable the multi-monitors option by typing in mstsc.exe-multimon and hitting Enter. 

Now that you're set up for multi-monitors, click the Windows and R buttons, and the Run prompt should appear. Type "mstsc.exe/multimon" and enter the appropriate credentials. 

You'll see that the box that shows all of your monitors are available to the remote session is automatically toggled on, but you must understand that this is only for a single session. Connection rules don’t get saved automatically on the machine, nor are your sign-in credentials, so this option is best for a one-off connection request. Another feature of the command line route is that you can customize the experience. One example is using the /f parameter to start the session in full-screen mode or /h and /w to determine the height and width. Sometimes tech support is all about the little things. If you'd like more information or want to add a bit extra to your use of parameters, you can get the complete list here from Microsoft's reference doc.

Manually changing the RDP file

This option is slightly more technical. By default, the connection settings get saved to the Documents folder in a hidden RDP file. So, you could instead open the file with a text editor and directly edit the values there to set up the multi-monitor remote connection. Here's what to do:

• Navigate to the Documents folder and ensure Show hidden items is enabled.

• Then, with a text editor, open the RDP file, add the following line, and then save the file: use multimon:i:1.

• You can also add additional security here by hiding specific monitors so they cannot be viewed from a remote machine over TCP. You do this using the string "selectedmonitors:s:x1,x2,x16", replacing the numbers with the ones you want to be viewed. The first number will be the primary monitor.

• If the display order is wrong, execute the mstsc /l command in CMD to view all the monitors on your system. They'll be listed as 0, 1, 2, and so on.

• Next, you can adjust the values for the selectedmonitors line to rearrange the monitors in the correct order. 

• For instance, if you have three monitors shown as selectedmonitors:s:0,1,2, you could amend it to selectedmonitors:s:1,2,0 to change the displayed order or selectedmonitors:s:0,2 to use 2 of the 3 monitors.

• Remember to save the settings once you figure out the correct order.

So that's our take on using remote desktop solutions with multiple monitors. Want to know about us? You can look at our marketplace for RDP integrations here, and don't forget to let us know what you think of this article in the comments.

* The quick assist conversation. 

• "Click on Quick Assist*. No, not Quick Setup Wizard, Quick Assist. No, not Skype. We don't use that anymore, remember? We have Teams now instead. OK, let's try this again. Type Start and then Quick Assist. The button that looks like a windows flag on the bottom left-hand corner of your screen."

• "I'm just going to need your computer name so that I can connect to you. Can you check your asset tag for me? Don't you have one? No worries - we can do it the old-fashioned way. Can you open up a command prompt, please? Click Start, Run, then type in CMD - no, not CND, CMD - Charlie Mike, Delta. No, your computer isn't broken - don't worry, that's what a command prompt looks like. It's all good; now all I need you to do is type in hostname and hit return. OK - I hear you when you say you hate the command prompt stuff. Let's try going into system settings instead. Click Start, type System Settings, and look for the Device Name field about one-third of the way down the page."

• "Can you click on the Accept button, please? Yes, I know we tell you not to accept connections from suspicious accounts, but I'm from the service desk. You called me, remember? Hello?"