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Error response from daemon: dockerfile parse error at line X

Docker couldn't parse your Dockerfile because of a syntax error. Every instruction must follow the format INSTRUCTION arguments, and certain rules apply — like not putting instructions before the first FROM, using proper line continuation, or using valid instruction names.

Common causes

  • An unknown or misspelled instruction keyword (e.g., COPIES instead of COPY)
  • A line continuation backslash \ with trailing spaces or a Windows-style CRLF line ending after it
  • Instructions appearing before the first FROM (except ARG, which is allowed before FROM)
  • An empty or malformed instruction line

How to fix it

  1. Read the error line number and check that line in your Dockerfile
  2. Ensure all instructions use valid keywords: FROM, RUN, COPY, ADD, ENV, EXPOSE, CMD, ENTRYPOINT, WORKDIR, ARG, LABEL, USER, VOLUME
  3. Convert Windows line endings to Unix: sed -i 's/\r//' Dockerfile, or use dos2unix Dockerfile
  4. Validate the Dockerfile with: docker build --check . (Docker 24+) or a linter like hadolint

Example

$ docker build . Error response from daemon: dockerfile parse error line 5: unknown instruction: COPIES

Typo in the Dockerfile — COPIES instead of COPY on line 5

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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