Docker not running
The manager interface opens, but starting a project fails at preflight.
Symptom
The dashboard loads and health reports a Docker warning. A project start fails, naming Docker or the daemon.
Cause
The Docker daemon is not running, or the current user cannot reach it. The manager runs without Docker by design; its projects cannot.
Fix
Check the daemon
Run the Docker info command and confirm it responds without a permission error.
docker infoStart Docker
Start Docker Desktop, or the Docker service on Linux, and wait for the engine to report ready.
On Linux, check the socket
If the command is denied, fix the user's Docker group membership rather than running the manager as root.
Retry the project start
Preflight runs again and should pass once the daemon is reachable.
Prevention
Start Docker before the manager when you intend to run projects. The prerequisites-only launcher check reports Docker status without starting anything.
Another thing to check
If Docker is running but a start still fails, check the project path and the port ownership next. The preflight error names the failing check, so read it rather than retrying the same start repeatedly.
In one sentence
Docker is a precondition for project starts, not for the manager interface; confirm the daemon first, then the path and the ports.