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ERROR: Version in "./docker-compose.yml" is unsupported

The version declared at the top of your docker-compose.yml isn't supported by the Docker Compose version you have installed. Compose file format versions map to specific Docker Engine and Compose versions, and using a newer format with an older tool causes this error.

Common causes

  • The version field in docker-compose.yml specifies a newer Compose file format than your installed version supports
  • An older Docker Compose v1 (docker-compose) is being used with a file written for Compose v2+ (docker compose)
  • The version string is malformed — it must be a quoted string like "3.9" not an unquoted number
  • Copying a docker-compose.yml from a newer environment to an older server

How to fix it

  1. Upgrade Docker Compose: on Linux, docker compose (the v2 plugin) comes with Docker Engine 20.10+
  2. If stuck on an older version, downgrade the version field to one your Compose supports: version: "3.7"
  3. Remove the version field entirely — in Compose v2, the version field is optional and ignored
  4. Check your installed version: docker-compose --version or docker compose version

Example

$ docker-compose up ERROR: Version in "./docker-compose.yml" is unsupported: 3.9

docker-compose.yml uses version '3.9' but the installed docker-compose only supports up to 3.7

Related Docker Errors

Cannot connect to Docker daemonPermission denied connecting to Docker socketDocker daemon not running on this hostImage not found or pull access deniedImage manifest not found (tag doesn't exist)

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