Microsoft RDP Extensions (MsRdpEx)

Installation

Download and install the latest MsRdpEx MSI package GitHub releases.

After installation, the launcher executables and API hooking DLL can be found in "%ProgramFiles%\Devolutions\MsRdpEx":

The installer automatically associates .RDP files with mstscex, and .RDPW files with msrdcex, so you can get started right away. Simply revert the file type association to use the original Microsoft Remote Desktop Clients without the extensions, or launch mstsc.exe/msrdc.exe manually.

This repository also contains a C# nuget package that can be used to consume the RDP ActiveX interface with or without API hooking, along with launching mstsc.exe or msrdc.exe as external processes using MsRdpEx.dll.

Extended .RDP File Options

MsRdpEx processes additional .RDP file options that are not normally supported by mstsc.exe:

RDP setting	Description	Values	Default value
KDCProxyURL:s:value	Kerberos KDC Proxy HTTPS URL	KDC Proxy HTTPS URL, not using error-prone KDCProxyName format, and unrestricted in length, like https://<hostname>:443/KdcProxy	-
UserSpecifiedServerName:s:value	Server name used for TLS and Kerberos server validation	explicit server name (usually the machine FQDN)	same as DNS hostname used for RDP server
EnableMouseJiggler:i:value	Enable RDP mouse jiggler	0/1	0
MouseJigglerInterval:i:value	RDP mouse jiggler interval in seconds	Interval in seconds	60
MouseJigglerMethod:i:value	RDP mouse jiggler method	0/1	0
AllowBackgroundInput:i:value	Allow background input events when window is not in focus	0/1	0
EnableRelativeMouse:i:value	Enable relative mouse mode	0/1	0
DisableCredentialsDelegation:i:value	Disable CredSSP credential delegation	0/1	0
RedirectedAuthentication:i:value	Enable Remote Credential Guard	0/1	0
RestrictedLogon:i:value	Enable Restricted Admin Mode	0/1	0
DisableUDPTransport:i:value	Disable RDP UDP transport (TCP only)	0/1	0
ConnectToChildSession:i:value	Connect to child session	0/1	0
EnableHardwareMode:i:value	Disable DirectX client presenter (force GDI client presenter)	0/1	1
ClearTextPassword:s:value	Target RDP server password - use for testing only	Insecure password	-
GatewayPassword:s:value	RD Gateway server password - use for testing only	Insecure password	-

Extended RDP client logs

MsRdpEx also supports extended logging controlled by environment variables:

powershellCopy
$Env:MSRDPEX_LOG_ENABLED="1"
$Env:MSRDPEX_LOG_LEVEL="DEBUG"
.\mstscex.exe <destination.rdp>

If you don't pass a .RDP file, the mstsc.exe GUI will launch normally, but you won't be able to leverage any of the extended MsRdpEx .RDP file options. The default log file path location is in "%LocalAppData%\MsRdpEx\MsRdpEx.log". You can override log settings using the MSRDPEX_LOG_LEVEL and MSRDPEX_LOG_FILE_PATH environment variables:

powershellCopy
$Env:MSRDPEX_LOG_ENABLED="1"
$Env:MSRDPEX_LOG_LEVEL="TRACE"
$Env:MSRDPEX_LOG_FILE_PATH="C:\Windows\Temp\MsRdpEx.log"
.\mstscex.exe

The trace log level is extremely verbose, so it should only be used when necessary. The MsRdpEx logging is very helpful in understanding the Microsoft RDP client internals.

Building from source

Generate the Visual Studio project files for your target platform:

powershellCopy
mkdir build-x64 && cd build-x64
cmake -G "Visual Studio 18 2026" -A x64 ..

Open the Visual Studio solution or build it from the command-line:

powershellCopy
cmake --build . --config Release

You should now have mstscex.exe and MsRdpEx.dll.