On Windows Vista 64 and Windows 7 64, there is a 32 bit version of Remote Desktop Connection (Microsoft Terminal Services Client, mstsc.exe) in %SystemRoot%\SysWOW64.
Running this mstsc.exe will launch the 32 bit process but it will instantly launch the 64-bit mstsc.exe from System32 and shut itself down. This makes it impossible to run Remote Desktop Connection . . . → Read More: Running 32-bit Remote Desktop Connection on Windows 64 bit