Patching termsrv.dll to bypass session limits directly violates the Microsoft Software License Terms. It should never be used in a production environment subject to corporate audits.
Use the command takeown /F c:\Windows\System32\termsrv.dll /A followed by icacls c:\Windows\System32\termsrv.dll /grant Administrators:F to get full permissions.
The two-session limit applies to both Server Standard and Server Datacenter editions. Only after installing the Remote Desktop Session Host (RDSH) role and properly licensing the server can organizations legally support more simultaneous connections.
Enabling a small team to work remotely without the high cost of official RDS CAL licensing. termsrv.dll patch windows server 2016
Create a backup of C:\Windows\System32\termsrv.dll and stop the Remote Desktop Services ( TermService ).
If you encounter errors after applying the patch, review these common troubleshooting scenarios:
This method uses the fabianosrc/TermsrvPatcher script, which simplifies the process. Patching termsrv
The patch targets specific binary instructions within the termsrv.dll file (located in C:\Windows\System32 ) that check for session limits.
However, this method only works if Windows Server 2016 detects the Remote Desktop Services role. Without proper licensing, the system may still enforce the two-session limit despite group policy adjustments.
Windows protects system files via the TrustedInstaller account. You must change the permissions. Open Command Prompt as an Administrator. Run the following command to take ownership: takeown /f C:\Windows\System32\termsrv.dll /a Use code with caution. Grant full control permissions to the Administrators group: The two-session limit applies to both Server Standard
This keeps the original file intact. However, because Windows updates frequently change termsrv.dll , you must consistently update the RDP Wrapper configuration file ( rdpwrap.ini ) to support newer Windows Server 2016 build versions. Risks, Considerations, and Legal Disclaimers
Automated patchers often modify registry keys ( AllowMultipleTSSessions ) and may disable licensing service triggers. Always check the source code if available.
Download the latest release architecture from a trusted repository (such as GitHub). Extract the files and run install.bat as an Administrator.
: This TermsrvPatcher repository provides a PowerShell script to automate the process and includes a Scheduled Task to re-apply the patch automatically after Windows Updates.