Option 1: OpenMoHAA (Recommended for Modern Systems)

OpenMoHAA is a modern, open-source reimplementation of the Medal of Honor: Allied Assault engine. It is compatible with the original game and its expansions (Spearhead and Breakthrough).

• Works natively on Windows, macOS, and Linux.
• Uplinks directly to the 333networks masterserver (no patching required).
• Requires original game files to play.

Option 2: Patching the Original Game (Windows)

If you prefer to use the original game client on Windows, you must patch it to replace the defunct GameSpy masterserver with 333networks.

Method A: Patched Binaries (Easiest)

Download the pre-patched executable for your game version and replace the original file in your game folder.

• MOHAA (v1.11): Replace MOHAA.exe with the patched version.
• Spearhead (v2.15): Replace moh_spearhead.exe with the patched version.
• Breakthrough (v2.40): Replace moh_Breakthrough.exe with the patched version.

Method B: HOSTS File Edit

Alternatively, you can edit your Windows HOSTS file to redirect the old masterserver address.

See 333networks for full instructions on this method.