The ActiveX DLL for Microsoft Terminal Services (the mstscax.dll file) resides in the %WINDIR%System32 directory. The ActiveX Importer (AXIMP.EXE), which is part of the .NET Framework component of the Windows SDK, generates two DLLs (MSTSCLib.dll and AxMSTSCLib.dll) from that ActiveX DLL.
The first DLL, MSTSCLib.dll, contains the managed definitions of the unmanaged interfaces, classes, structures, and enums, defined in the type library contained inside the ActiveX DLL (mstscax.dll). This is generally named with the library name from the original type library.
The second DLL, AxMSTSCLib.dll, is named the same but with an Ax prefix. This contains a Windows Forms control corresponding to each ActiveX class. The Windows Forms representation of the ActiveX control is added to WindowsFormsHost.
In our example, the AxMsTscAxNotSafeForScripting control is used in XAML, inside WindowsFormsHost, to perform the interaction. Its Server property, from the code behind the class, has...