Since it is a system file, you must take ownership from TrustedInstaller using takeown /F "%windir%\system32\termsrv.dll" /A .
The patch typically involves replacing or modifying the termsrv.dll located in C:\Windows\System32 . universal termsrvdll patch windows server 2012 r2 top
Provides a workaround for environments that need multiple access points without immediately investing in full Remote Desktop Services (RDS) Client Access Licenses (CALs). Since it is a system file, you must
Replace the original file with the patched version or run a dedicated patcher like Universal Termsrv.dll Patch 1.0b . Since it is a system file
Use Net stop TermService in an elevated Command Prompt.
Restart the service with Net start TermService . Important Considerations & Alternatives
Allows for the use of "Remote Apps," enabling users to launch specific applications in a seamless window rather than a full desktop session. Installation & Usage