Instead of patching termsrv.dll , consider these Microsoft-supported options for multiple RDP sessions:
The immediate attraction of the Termsrv.dll patch is obvious: it is free. For developers, students, homelab enthusiasts, or small businesses testing applications in a sandbox, paying hundreds or thousands of dollars for RDS CALs is prohibitive. The patch enables them to simulate a multi-user environment on a single Windows Server 2022 instance—perfect for training labs, software prototyping, or light internal tools. The process is relatively simple: take ownership of the file, stop the RDP service, replace the patched DLL, and restart. Within minutes, a standard Windows Server 2022 machine becomes a "terminal server" without official licensing. Termsrv.dll Patch Windows Server 2022 -FREE-
Patching system files is a violation of Microsoft's licensing agreement and is intended for lab or testing environments only. Always create a copy of your original termsrv.dll located in C:\Windows\System32\ before making changes. Instead of patching termsrv