Hello and welcome, my fellow tele-toilers and anyone just scrolling by!
Operating a computer with multiple monitors connected to it is a very common practice these days. And setting up remote connections to those machines can be a lot trickier than one may think. That’s why I’ve decided to make a HelpWire blog focused on using a standard Windows RDC app called Remote Desktop Connection to access dual-monitor machines.
Well, actually, the method I’m about to introduce you to, will work just fine for three, four, and even sixteen monitors at the same time. And the connections are possible not only between physical computers, but virtual machines as well, i.a. Azure-based systems.
Sounds exciting? Alrighty then, let’s roll!
Accessing multiple monitors during an RDP session
A quick note before we start: Sadly, with the standard Windows Remote Desktop app, you can’t change your connection properties mid-session. So for any adjustments to take effect, you’ll have to terminate all on-going RDP connections.
Ok, without further due, here are the instructions for all three ways to enable multi-monitor support for the Windows Remote Desktop application on your RDC server:
1. Type ‘remote connection’ into the system search box to launch the app.
2. Enter your authentication credentials, then click the Show Options button in the bottom-right corner:
3. Now, go to the Display tab and tick the ‘Use all my monitors for the remote session’ checkbox (DO NOT click the connect button, we have some more settings to tweak with):
4. Go back to the General tab and click the Save as… button, so you won’t have to repeat all these steps every time you need to access this machine from remote PCs. Also, it’s a very good idea to remember or write down the folder you save the ROP file to as you may need to make some adjustments to it later (e.g., to make one of your monitors invisible from remote desktops).
Press Win+R on your keyboard to involve the Run window and type: mstsc.exe /multimon. The “Use all my monitors for the remote session” box will be checked automatically, but for this time only. Neither the connection properties nor your credentials will be saved on this machine. So if you plan to have more remote desktop sessions here, or this is one of your RDP servers, better go for one of the other two methods.
Open your RDP file (by default, it’s in system32) with the Notepad or drag-and=drop it to the browser window, and add the line to it as follows:
On top of that, you can add another string here to hide some of your monitors so that they won’t be visible over TCP from any remote machine:
Replace x1…16 with the actual numbers of the monitors you have. The first number indicates the primary monitor.
Important note: The display’s number is not necessarily the same one you’ll see in your system monitor properties. To obtain the correct ones, use the mstsc/l command.
Don’t forget to save the file before closing.
All three methods I’ve just described will also work for Linux and iOS machines, given that you have the correct Remote Desktop versions installed there too. But you should note that all the methods described above only apply to the standard RDP app. The newer black-interfaced one you can get from the Microsoft store has no multi-monitor support whatsoever.
Known connectivity issues
As I’ve mentioned before, you won’t have any problems with accessing non-Windows multi-monitor desktops. However, it’s not that easy when it comes to linking up computers with different Windows versions, especially when you try to connect to older systems from a newer one.
For Windows 7 machines, multi-monitor mode is only available for Enterprise or Ultimate builds. If you’re going to connect a Windows 8.1 machine, make sure it has a Professional or Enterprise build. And as for Windows Server builds, both Standard and Datacenter editions of Win 2008, 2012, and 2016 can be connected in multi-monitor mode from whatever other Windows versions you have.
Span mode specifics
On top of everything we’ve just discussed, Remote Desktop has another feature you can use to connect a PC with multiple monitors. This feature was introduced in Windows Vista as an alternative to multi-monitor mode but never gained any popularity. My best guess is that no one liked it because of some restrictions it has. But it’s worth a mention here nevertheless.
To put it simply, instead of showing you every remote monitor in a separate window, this mode just tries to fit them all in one. And fail miserably nine times out of ten because not all monitor set-ups fit in a rectangle.
Here is a picture with some examples:
As you can see, this mode is not even worth trying unless all your monitors share exactly the same vertical resolution. But if that’s your case, here is what you need to do to set it up:
Hit Win+R on your keyboard to invoke the Run command box and enter mstsc/span.
Note that the session that will start after you press Enter will be a single-monitor session, not a multi-monitor one.
Known usability issues
Yet another hidden reef of the standard Remote Desktop application is its tendency to lag a lot on the newest Windows 10 versions. Actually, it tends to freeze so much it’s hardly usable at all.
Here is what you can do to try and fix this issue:
1. The first thing you do is disable UDP for the client. To do this, launch Regedit and go to Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows NT\Terminal Services\Client.
Here you’ll need to create a DWORD with the name fClientDisableUDP and assign it a value of 1.
2. Then open the Remote Desktop settings and disable smart card passthrough.
Some so-called experts recommend disabling your VPNs too, but I strongly advise not to. If these two steps didn’t work for you, just ditch standard apps and get yourself a proper software tool to use the RDP technology to the fullest.
And that’ll be all for today. Don’t hesitate to click my links to dig a bit deeper, stay safe, always remember that VPN is your best friend, and see ya all in the following blogs.