Download of Multi Crew Experience 2.6.3.1 was on the developer's website when we last checked. We cannot confirm if there is a free download of this software available. The actual developer of the software is FS++ Simulations. The software lies within Games, more precisely Simulation.
You can launch this PC program on Windows XP/Vista/7/8/10/11 32-bit. We recommend checking the downloaded files with any free antivirus. The following versions: 2.6, 2.5 and 2.4 are the most frequently downloaded ones by the program users. The common filenames for the program's installer are MCE-Launcher.exe, mce.exe or xpmce.exe etc.
From the developer:
Multi Crew Experience is an add-on designed to work with FSX and FS 2004 simulators that allows you to talk not just to your co-pilot, but to native ATC, Radar Contact controllers, as well as Pro Flight Emulator ATC controllers. You will be able to interact with the built-in FS ATC in English.
You may want to check out more software, such as Multi-Terr, Multi Zone Audio Player or Experiance index editor, which might be similar to Multi Crew Experience.