: Add the Remote Desktop Services role via Server Manager. Deploy Licensing : Install the RD Licensing role service.
By default, Windows Server (in non-RDS mode) and Windows 10/11 allow only one active RDP session. If a second user logs in, the first is kicked off. Patching termsrv.dll
Note: Windows Update frequently breaks RDP Wrapper by changing the internal offsets in termsrv.dll . When this happens, you must update the rdpwrap.ini configuration file with the newest offsets for your build. Troubleshooting Common Issues The "Remote Desktop Service is Busy" Error
: Manually modifying system binaries can introduce vulnerabilities. Furthermore, using "pre-patched" DLLs from the internet is highly discouraged as they may contain malware or backdoors. Compliance : From a licensing perspective, patching termsrv.dll windows server 2019 termsrvdll patch patched
You must take ownership of the file and grant your user account Full Control permissions.
Windows protects system files by assigning ownership to the TrustedInstaller account. You must change ownership to the Administrators group. 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.
This information is for educational purposes only. Always use authorized methods in production environments. Patching Microsoft's RDP service yourself - Sam Decrock : Add the Remote Desktop Services role via Server Manager
In the ecosystem of system administration, few modifications are as simultaneously alluring and perilous as the unofficial patching of termsrv.dll in Windows Server 2019. This dynamic link library file is the engine behind Remote Desktop Services (RDS), the component that allows multiple users to connect simultaneously to a server’s graphical interface. On a licensed Windows Server, the default behavior of termsrv.dll enforces a strict two concurrent administrative session limit—unless the appropriate RDS Client Access Licenses (CALs) are installed. To circumvent this, a well-known but unsupported patch has emerged, promising to unlock unlimited concurrent sessions. While technically effective, applying this patch transforms a production server into a legal and stability minefield.
Step-by-Step Guide to Patching termsrv.dll on Windows Server 2019
. A patch that works today may cause the RDP service to crash or fail to start after next Tuesday's update. If a second user logs in, the first is kicked off
For Windows Server 2019 (build 17763), community tools and scripts emerged that automatically patched termsrv.dll and replaced the protected file after taking ownership.
: Replacing system DLLs with files downloaded from untrusted sources is a major security risk. Always use a reputable script or perform the hex edit yourself. 🚀 How to Verify
To legally and reliably exceed two concurrent RDP sessions on Windows Server 2019:
Look for the following criteria depending on your exact build version: Search for Hex String: 39 81 3C 06 00 00 0F 84 Replace with Hex String: B8 00 01 00 00 90 89 41 Common Pattern 2 (Updated Builds / 1809): Search for Hex String: 39 81 3C 06 00 00 74 B3 Replace with Hex String: B8 00 01 00 00 90 90 90
: A standard Windows Update will overwrite your patched file with the official version, immediately breaking multi-user access.
