Two primary tools are used in the community to automate this process:
icacls C:\Windows\System32\termsrv.dll /grant Administrators:F Use code with caution. Step 2: Stop the Remote Desktop Service
Windows Updates often overwrite termsrv.dll . If the patch is incompatible with a new version, the RDP service may fail to start, locking you out of the server.
If you prefer not to touch hex code, the open-source project acts as a layer between the Service Control Manager and TermService. Instead of modifying termsrv.dll on your hard drive, it patches the file in-memory. Step 1: Download the Files
: Ensure you are logged in with a local administrator account. termsrv.dll patch windows server 2016
After replacing or editing the file, restore the system services.
The termsrv.dll file is the core component of Remote Desktop Services (formerly Terminal Services) on Windows systems. It manages user sessions, authentication, and connection limits. The file is located in %SystemRoot%\System32\ .
termsrv.dll on Windows Server 2016 is a common workaround to enable more than two concurrent Remote Desktop (RDP) sessions without installing the full Remote Desktop Services (RDS) role and purchasing client access licenses (CALs). Primary Methods to Enable Concurrent Sessions RDP Wrapper Library (Recommended)
For testing, lab environments, or budget-constrained setups, modifying the termsrv.dll file removes this session limit. This guide explains how the patch works, how to implement it safely, and the risks involved. Understanding termsrv.dll and the Session Limit Two primary tools are used in the community
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The safest but most difficult way; involves taking ownership of the file and manually changing hex values (e.g., changing 39 81 3C 06 00 00 0F 84 sequences).
Understanding and Applying the termsrv.dll Patch on Windows Server 2016 If you prefer not to touch hex code,
Is this for a , or is it a production server ?
On Windows Server 2016, this file enforces the two-session limit for administrative connections. Modifying, or "patching," this file alters the hex code responsible for checking the session limit, effectively allowing an unlimited number of concurrent RDP connections. Crucial Prerequisites and Risks
: Because this involves modifying a core Windows file, system updates or tools like sfc /scannow
After this signature, there are four subsequent bytes that vary depending on the exact build number of the DLL (for example, in build 17763.1697 you might see A1 8F 01 00 ). Replace the entire sequence ( 39 81 3C 06 00 00 0F 84 [four bytes] ) with: