Age of Empires II: The Conquerors vs. The Kings – No Cross-Version LAN Play

No. Age of Empires II: The Age of Kings (base game) and The Conquerors (expansion) are separate executables with different engines/data. They cannot connect via LAN or Internet for multiplayer.

Solutions

1. Both players use the same version: Upgrade the Age of Kings player to The Conquerors (often <$5 on Steam/GOG sales). This is the only reliable path.
2. Use Voobly / GameRanger / Steam Lobby: These services match players *within the same version*. They don't bridge versions.
3. Play the "Definitive Edition" (Steam): Both players buy Age of Empires II: Definitive Edition – unified player base, cross-play (PC/Xbox), modern netcode, all civs/campaigns included.

Definitive Edition is the best experience today. The original CDs are abandonware for multiplayer purposes.