Option 1 - Modifying termsrv.dll

To have concurrent user sessions working in Windows 10, you need to make small changes to termsrv.dll file. This file is located in C:WindowsSystem32 folder. Before modifying termsrv.dllfor the first time, you need to take ownership and assign yourself full permissions. You also need to stop Remote Desktop service (TermService) if it's running.

I just got a new machine with Win10 Enterprise and I am trying to set it up to support multiple instances of simultaneous Remote Desktop Connections. At this point, multi-session Remote Desktop Services (RDS) is a Windows Server-only feature, one that lets users run applications hosted on servers, whether the servers are on-premises or cloud-based.

DLL files can be modified using any HEX Editor (for example Tiny Hexer). You can do this yourself by replacing strings shown below, or just download patched versions from this page.

Windows 10 x64 v2004 - May 2020 Update (20H1)

After this update termsrv.dll is upgraded to version 10.0.19041.84 To get back concurrent remote desktop connections, make the following changes:

Find:

39 81 3C 06 00 00 0F 84 D9 51 01 00

replace with:

B8 00 01 00 00 89 81 38 06 00 00 90

The patched version can be download from here. The original, v10.0.19041.84 file can be found here.

Older Windows 10 versions

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Windows 10 x64 v1909 - November 2019 Update

After this update termsrv.dll is upgraded to version 10.0.18362.657. To get back concurrent remote desktop connections, make the following changes:

Find:

39 81 3C 06 00 00 0F 84 5D 61 01 00

replace with:

B8 00 01 00 00 89 81 38 06 00 00 90

The patched version can be download from here. The original, v10.0.17763.1 file can be found here.

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Windows 10 x64 v1903 - May 2019 Update

After this update termsrv.dll is upgraded to version 10.0.18362.53. To get back concurrent remote desktop connections, make the following changes:

Find:

39 81 3C 06 00 00 0F 84 5D 61 01 00

replace with:

B8 00 01 00 00 89 81 38 06 00 00 90

The patched version can be download from here. The original, v10.0.17763.1 file can be found here.

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Windows 10 x64 v1809 - October 2018 Update + Cumulative April 2019 Update

After this update termsrv.dll is upgraded to version 10.0.17763.437. To get back concurrent remote desktop connections, the make the following changes:

Find:

39 81 3C 06 00 00 0F 84 3B 2B 01 00

replace with:

B8 00 01 00 00 89 81 38 06 00 00 90

The patched version can be download from here. The original, v10.0.17763.437 file can be found here.

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Windows 10 x64 v1809 - October 2018 Update

Windows 10 October 2018 Update (1809) updates termsrv.dll to version 10.0.17763.1. To get back concurrent remote desktop connections, the make the following changes:

Find:

39 81 3C 06 00 00 0F 84 7F 2C 01 00

replace with:

B8 00 01 00 00 89 81 38 06 00 00 90

The patched version can be download from here. The original, v10.0.17763.1 file can be found here.

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Windows 10 x64 v1803 - Spring 2018 Update (March 2018)

Windows 10 Spring 2018 Update (1803) updates termsrv.dll to version 10.0.17134.1. To get back concurrent remote desktop connections, make the following changes:

Find:

8B 99 3C 06 00 00 8B B9 38 06 00 00

replace with:

B8 00 01 00 00 89 81 38 06 00 00 90

The patched version can be download from here. The original, v10.0.17134.1 file can be found here.

Windows 10 Multi Session Rdp

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Windows 10 Fall Creators Update (1709 - Redstone 3)

Updates termsrv.dll to version 10.0.16299.15. To get back concurrent remote desktop connections, make the following changes:

Find:

39 81 3C 06 00 00 0F 84 B1 7D 02 00

replace with:

B8 00 01 00 00 89 81 38 06 00 00 90

The patched version can be download from here. The original, v10.0.16299.15 file can be found here.

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Windows 10 x64 v1703 - Creators Update (April 2017)

Windows 10 Creators Update (1703 - Redstone 2) updates termsrv.dll to version 10.0.15063.0. To get back concurrent remote desktop connections, make the following changes:

Find:

39 81 3C 06 00 00 0F 84 53 71 02 00

replace with:

Windows Multiple Remote Desktop

B8 00 01 00 00 89 81 38 06 00 00 90

The patched version can be download from here. Original, v10.0.15063.0 file can be found here.

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Windows 10 x64 Threshold 2 (November 2015)

Windows 10 Fall Update (also called 'Threshold Wave 2 Update') updates termsrv.dll to version 10.0.10586.0. To get back concurrent remote desktop connections, make the following changes:

Find:
39 81 3C 06 00 00 0F 84 3F 42 02 00

replace with:
B8 00 01 00 00 89 81 38 06 00 00 90

The patched version can be download from here. Original, v10.0.10586.0 file is here.

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Windows 10 x64 RTM (August 2015)

termsrv.dll file version 10.0.10240.16384.

In termsrv.dll find:
39 81 3C 06 00 00 0F 84 73 42 02 00

and replace it with:
B8 00 01 00 00 89 81 38 06 00 00 90

The patched version can be downloaded from here. The original, untouched version of termsrv.dll v10.0.10240.16384 can be downloaded from here.

Option 2 - RDP Wrapper

Instead of modifying termsrv.dll file you can use RDP Wrapper which acts as a middleman between Terminal Services and Service Control Manager. This way you don't need to touch termsrv.dll file. Actually, if you already modified your termsrv.dll file, you need to revert to the original version before using this method.

Download and extract RDPWrap-v1.6.1.zip (or newer), then run install.bat as admin. After installation is completed, run RDPConfig.exe. If all items under Diagnostics are green, you should be good to go.

If 'Listener state' is 'Listening [not supported]', you will need to update the wrapper's configuration (.ini) file.

With the latest version of RDP Wrapper you no longer need to update rdpwrap.ini manually. Simply run update.bat and everything will be done automatically.

If update.bat doesn't add support to your Windows version, try checking Open Issues on RDP Wrapper GitHub page. You may find how to manually update rdpwrap.ini until official support is added.

May 2017
Windows 10 64bit

This blog post introduces Windows 10 Enterprise multi-session as a new Remote Desktop Session Host (RDSH) exclusively for Windows Virtual Desktop. It also provides step-by-step instructions on how to create a Windows 10 multi-session template from the Parallels® Remote Application Server (RAS) Console.

In addition to supporting multiple concurrent interactive sessions, there are additional differences between Windows 10 Enterprise multi-session and other Windows 10 single-session versions. The main features of Windows 10 Enterprise multi-session are listed below:

• Availability and support: Windows 10 Enterprise multi-session can be found in the Azure Gallery, and it is available through the Azure Windows Virtual Desktop service and from the Parallels RAS Console, which is able to read the marketplace images. Microsoft does not support it on non-Azure deployments.
• License eligibility: An eligible Windows or Microsoft 365 license provides access to Windows 10 Enterprise desktops and applications. Organizations can use existing per-user Windows licensing instead of Remote Desktop Services (RDS) Client Access Licenses (CALs). View a full list of applicable licenses.
• Session limits: There are no limits regarding how many interactive sessions can be active over a host simultaneously. This number will be estimated by administrators analyzing the host’s resources as well as the system’s workload, which is generated by the applications running concurrently.
• Compatibility: It reports Windows Server as ProductType, meaning that this OS is compatible with management tools, OS optimizations and applications that have already been used for RDSH environments.
• Profiles: Microsoft recommends the use of FSLogix Profile Containers when using this OS in non-persistent environments that need a centrally stored profile.

Parallels RAS extends and enriches Windows Virtual Desktop capabilities by integrating all virtual workloads and resources centrally. However, Windows Virtual Desktop integration is not enabled by default. To enable it from the Parallels RAS Console, follow the subsequent steps:
1. Navigate to Farm > Site > Settings, select the Features tab and locate the Windows Virtual Desktop section at the bottom of the page.

2. Check the Enable WVD management checkbox.

3. Click Download to get the current version of WVD Agent and BootLoader, saving them on either the Publishing Agent or a Network share. Once both are downloaded successfully, Status is marked as Available and the Current Version is displayed, as shown in the screenshot above.

4. The Client feature set selection specifies which client features will be available when a published resource in Parallels Client is opened.

Prior to creating a Windows 10 multi-session template, administrators must configure the connection between their Parallels RAS setup and an Azure Subscription by adding a new Windows Virtual Desktop provider. A Microsoft Azure Tenant ID, Subscription ID, Application ID, and a secret key need to be provided.

Once the provider has been added, navigate to Farm > Site > Windows Virtual Desktop, select the Templates tab and click (+) to open the Create Parallels Template Wizard.
1. On the first page, select Windows Virtual Desktop as the Provider and choose Multi-session as the Template Type. Then, click Next.

2. On the Template Source page, select any of the available Windows 10 Enterprise multi-session versions from the Azure Gallery window. Enter the credentials for the Local administration account. Click >Next.

The Custom host option for Source displays a list of pre-created virtual machines, which can also be Windows 10 multi-session, whereas the Browse all images button opens a dialog to choose any other image from the Marketplace or Shared Image Gallery.

3. On the Properties page, complete the following fields as needed: Template Name, Number of hosts to deploy on wizard completion, Maximum number of hosts, Create an availability set, and Host prefix. Then click Next.

4. On the Settings page, specify the values for the Keep available buffer, Host power state after the preparation, and Delete unused hosts after fields. Click Next.

5. On the Hosts page, select virtual machine properties from the predefined Azure values for Resource Group, VM Size, OS disk type, Virtual network and Subnet. Then click Next.

6. Select the Optimization settings. By default, these settings are inherited from Site defaults, but custom settings can also be specified.

7. On the Preparation page, select an imagepreparation tool and specify the required options.

8. On the Summary page, review all the defined settings and click on the Finish button to create the template.

Once a template has been created, it can be assigned to a host pool either when the pool is created or by editing the properties of a previously created host pool.

1. The Provisioning step of the Add Windows Virtual Desktop Host Pool wizard allows administrators to choose Template as a provisioning type. If this method is selected, a template can be chosen from the list of already existing templates.

Multi User Windows 10 Remote Desktop

To view and modify the properties of an existing host pool, navigate to Farm > Site > Windows Virtual Desktop, select the Host pools tab and locate the host pool to be modified. Right-click on it and choose Properties. In the dialog box that opens (shown below), select the Autoscale tab, and choose a template through the Select Template drop-down menu.

2. The next steps would be to publish Windows Virtual Desktop resources, applications or desktops, and configure user assignment and filtering rules. Once this process has been carried out, entitled users will be able to access a Windows 10 multi-session desktop from their Parallels Client.

Windows 10 Enterprise Multi User Remote Desktop

3. To view and manage Windows Virtual Desktop sessions, navigate to Farm > Site > Windows Virtual Desktop and select the Sessions tab. Sessions from all hosts in all host pools are displayed in the list.

Multi User Windows 10 Remote Desktop Service

Note that Parallels RAS allows for centrally managed end-user sessions running over Windows Virtual Desktop session hosts, including different task execution such as Disconnect, Log off, Remote control or Show processes. The Show information option opens an information dialog where session properties are grouped by functionality.

Rdp Windows 10 Multi User

Parallels RAS supports hybrid and cloud models, providing enterprises the flexibility to leverage these alternatives according to their technological and economic requirements. By using Parallels RAS, organizations can build the desktop and application delivery solution that best fits their needs. This can be achieved by combining the use of RDSH, VDI and Windows Virtual Desktop workloads and optimizing costs with a superior management experience from a single administration point. A fully functional, 30-day trial version of Parallels RAS can be deployed from the Microsoft Azure and Amazon AWS marketplaces.
Sources: https://www.parallels.com/blogs/ras/remote-desktop-multiple-users-windows-10/