diff --git a/player.h b/player.h
--- a/player.h
+++ b/player.h
@@ -252,7 +252,6 @@ static inline bool IsValidPlayer(PlayerI
 	return pi < MAX_PLAYERS;
 }
 
-void DeletePlayerWindows(PlayerID pi);
 byte GetPlayerRailtypes(PlayerID p);
 
 /** Finds out if a Player has a certain railtype available */