Before touching the DLL, you must stop the service that uses it.
This method gives you full control and works across all Server 2016 builds.
To maintain system integrity, you should return ownership to TrustedInstaller.
You cannot modify termsrv.dll because Windows protects it. You must claim ownership. termsrv.dll patch windows server 2016
RDP Wrapper (https://github.com/sebaxakerhtc/rdpwrap) works by loading a custom DLL (rdpwrap.dll) and an INI configuration file (rdpwrap.ini) that contains patching patterns for various termsrv.dll versions.
Advantages over direct patching:
For Windows Server 2016:
Check status with RDPCheck.exe (bundled). If it shows "Listening on port 3389" and "Supported" with unlimited connections, you succeeded.
From different PCs or using mstsc /admin variations, try opening 3+ concurrent RDP connections.
For IT administrators, developers, and tech enthusiasts who manage Windows Server 2016 machines, one limitation stands out as a persistent thorn in the side: the stringent two concurrent Remote Desktop Protocol (RDP) session limit. Before touching the DLL, you must stop the
Windows Server 2016, by default, allows only two simultaneous administrative remote connections. This is by design—Microsoft intends this for light server management, not for multi-user access scenarios. However, in lab environments, development servers, legacy application hosting, or even small businesses on a budget, the need for more than two concurrent users arises frequently.
Enter the termsrv.dll patch—a community-driven, unofficial modification that has been a rite of passage for Windows Server administrators for generations (from Windows 2000 to Windows Server 2019). This article provides an exhaustive, technical, and practical guide to applying the termsrv.dll patch on Windows Server 2016, including what it is, how it works, step-by-step instructions, risks, alternatives, and post-patch management.