Manually editing the binary code using a hex editor is the safest method. It ensures you use your server's original, trusted file rather than a downloaded replacement. Step 1: Stop the Remote Desktop Service
To enable multiple concurrent user sessions without purchasing Remote Desktop Services Client Access Licenses (RDS CALs), administrators often patch the termsrv.dll file. This guide explains how the patch works, how to implement it, and the associated risks. ⚠️ Important Warning and Legal Disclaimer
: Download a reliable hex editor like HxD if you plan to modify the file manually. Step-by-Step Guide to Patching termsrv.dll termsrv.dll patch windows server 2016
Windows protects system files with ci.dll (Code Integrity). To use a modified DLL, either:
: The modification typically replaces a check for the session limit with a command that always returns "true" or sets a higher limit. Technical Breakdown: How to Patch Manually editing the binary code using a hex
For Windows Server 2016 (Build 14393), typical hex changes include: Find: 39 81 3C 06 00 00 0F 84 D3 DE 02 00 Replace: B8 00 01 00 00 89 81 38 06 00 00 90 .
Stop the Remote Desktop Services ( TermService ) service. This guide explains how the patch works, how
icacls C:\Windows\System32\termsrv.dll /grant Administrators:F Use code with caution. Step 3: Backup the Original File
: Microsoft updates routinely replace modified system files with factory versions.
Open regedit and check: HKLM\SYSTEM\CurrentControlSet\Control\Terminal Server fDenyTSConnections should be 0 . (If AllowMultipleTSSessions exists, set to 1 .)