Docker: 'OCI runtime create failed: runc create failed: unable to start container process: exec: "...": executable file not found in $PATH' - how do I fix it?

Cause: Docker started the container but could not find the program named in ENTRYPOINT, CMD or the docker run command inside the image. Docker's exit codes help here: 127 means the command couldn't be found, 126 means it exists but can't be invoked (for example a directory or a file without execute permission). Typical reasons: the binary isn't installed in the final image (common with multi-stage builds or slim/distroless bases); a typo or wrong path; a script copied from Windows with CRLF line endings so the shebang interpreter is not found; a binary built for the wrong libc/architecture; a script that lacks the execute bit; or the command is written as one string in exec form (CMD ["python app.py"]) so Docker looks for a program literally called that. Fix (best first): 1. Write each argument as its own element in exec form: CMD ["python","app.py"], not CMD ["python app.py"]. 2. Inspect the image: docker run --rm -it --entrypoint sh <image> and check which <tool> and ls -l /path/to/file. If the image has no shell, use a debug variant or inspect the filesystem from a build stage. 3. Make sure the executable is copied into the final stage of a multi-stage build and installed under a directory on PATH, or use an absolute path like /usr/local/bin/myapp. 4. Make scripts executable (RUN chmod +x /entrypoint.sh or COPY --chmod where supported) and use LF line endings. Add a valid shebang such as #!/bin/sh that exists in the image. 5. Exec form doesn't use a shell, so shell features such as variables, pipes and && won't work; call ["sh","-c","..."] explicitly if you need them. 6. Check the image architecture matches the host. Verify: docker run --rm <image> starts the intended program, and the exit code is no longer 126 or 127. Sources: https://docs.docker.com/engine/containers/run/ https://docs.docker.com/reference/dockerfile/