The Past Ain't What It Used To Be...
The first Command & Conquer received its last official update on the 21st of June, 1996. Since then, the game has been ported to Windows (as "Gold" version), and re-released in the big "The First Decade" collection pack, but has never received any more bug fixes.
The C&C Gold Patch 1.06 project aims at bringing this classic into the new millennium, by fixing the old bugs, supporting higher resolutions, and adding new modding and mapping possibilities. It also contains an addon-based language system, allowing anyone to create translation packs for the game.
This is the message that is shown when you switch to a map which supports less players than the amount that has already joined the game, and then try to start it.
This is obviously forced though; I removed all but one start point from the map, and disabled the check for the minimum of 2 on the maps read, so it would accept a 1-player map.