Troubleshooting (36)

Last updated Sep 1, 2026 If you are using Media Transformations to transform your video and you experience a failure, the response body contains an error message explaining the reason, as well as the Cf-Resized header containing err=code:

  • 9401 — The required options are missing or are invalid. Refer to Options for supported arguments.
  • 9402 — The video was too large or the origin server did not respond as expected. Refer to source video requirements for more information.
  • 9404 — The video does not exist on the origin server or the URL used to transform the video is wrong. Verify the video exists and check the URL.
  • 9406 & 9419 — The video URL is a non-HTTPS URL or the URL has spaces or unescaped Unicode. Check your URL and try again.
  • 9407 — A lookup error occurred with the origin server's domain name. Check your DNS settings and try again.
  • 9408 — The origin server returned an HTTP 4xx status code and may be denying access to the video. Confirm your video settings and try again.
  • 9412 — The origin server returned a non-video, for example, an HTML page. This usually happens when an invalid URL is specified or server-side software has printed an error or presented a login page.
  • 9504 — The origin server could not be contacted because the origin server may be down or overloaded. Try again later.
  • 9509 — The origin server returned an HTTP 5xx status code. This is most likely a problem with the origin server-side software, not the transformation.
  • 9517 & 9523 — Internal errors. Contact support if you encounter these errors.

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