TestContainer stopped working after updating Docker Desktop to v4.56.0

[meyay (Metin Y.)]

Testcontainers 1.20.6 was released in May 2025. It does not work out of the box with Docker Engine v29, which is used by Docker Desktop since version 4.52.0.

I would put my money on: the testcontainers version used, by default uses an api version that is smaller than the min-api version 1.44 docker v29 requires by default.

You can set the api version in the docker-java.properties of your project:

Docker 29 increased minimum API version, breaks Traefik reverse proxy

Judging by the sources, the docker-java dependency in version 3.5.1 should already support api-version 1.44: The solution for you might be as easy, as setting api.versionin the docker-java.properties: https://github.com/docker-java/docker-java/blob/main/docs/getting_started.md#properties-docker-javaproperties

Or you can modify the daemon.json to unlock an older api version:

Portainer problem in windows docker 4.52.0

So apparently seeing this was not enough: [image] I should have clicked the endpoint. The problem is not the docker.sock. The problem is that portainer does not support the min API version v1.44 docker v29 requires. If you configure the min API version to 1.24, portainer will work again: open Docker Desktop settings → Docker Engine add property min-api-version": "1.24" click “Apply & restart” to restart the Docker Engine Now Portainer will work again. The resulting daemon configuration …