Multiple remote desktop sessions on a Windows machine

To allow multiple remote desktop sessions on a Windows machine, you typically need to adjust the Remote Desktop Services (RDS) configuration. By default, Windows Pro and Enterprise editions allow only one remote desktop session at a time. However, with some adjustments, you can enable multiple concurrent sessions.

Here’s how you can do it:

Method 1: Using Group Policy Editor (for Windows Pro/Enterprise)

1. Open Group Policy Editor:
   • Press Win + R, type gpedit.msc, and press Enter.
2. Navigate to Remote Desktop Settings:
   • Go to:
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     Computer Configuration > Administrative Templates > Windows Components > Remote Desktop Services > Remote Desktop Session Host > Connections

3. Enable Multiple Sessions:
   • Look for the policy named “Restrict Remote Desktop Services users to a single Remote Desktop Services session”.
   • Double-click it, set it to Disabled, and click OK.
4. Set the Limit of Connections:
   • In the same folder, find the policy named “Limit number of connections”.
   • Double-click it, set it to Enabled, and specify the maximum number of simultaneous connections you want to allow.
5. Apply Changes:
   • Close the Group Policy Editor and restart your computer for the changes to take effect.

Method 2: Modify the Termsrv.dll File (Not Recommended)

This method involves patching the termsrv.dll file to allow multiple sessions. However, this is unsupported by Microsoft and may violate licensing terms. Proceed with caution.

1. Take Ownership of termsrv.dll:
   • Navigate to C:\Windows\System32 and take ownership of the termsrv.dll file.
2. Make a Backup:
   • Copy the termsrv.dll file to a safe location as a backup.
3. Patch the File:
   • Use a hex editor or a pre-made patcher tool to modify the file to allow multiple sessions.
4. Restart the System:
   • After modifying the file, restart your computer.

Method 3: Use Windows Server (Recommended for Multiple Users)

If you need to allow multiple remote desktop sessions for multiple users, consider using Windows Server with the Remote Desktop Services (RDS) role installed. This is the official and supported way to enable multiple concurrent sessions.

1. Install Windows Server.
2. Add the Remote Desktop Services Role:
   • Use Server Manager to install the RDS role.
3. Configure Licensing:
   • Ensure you have the appropriate Remote Desktop Client Access Licenses (RDS CALs).

Important Notes:

• Licensing: Enabling multiple remote desktop sessions on a non-server version of Windows may violate Microsoft’s licensing terms. Ensure you comply with licensing requirements.
• Security: Allowing multiple remote sessions can expose your system to security risks. Use strong passwords and enable Network Level Authentication (NLA).