---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/17503#article
headline: "17503: Invalid mediaUrl (unsupported scheme or malformed)"
url: https://www.twilio.com/docs/api/errors/17503
inLanguage: en
dateModified: 2026-07-30T15:34:51.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 17503: Invalid mediaUrl (unsupported scheme or malformed)

Log Type: APPLICATION

Log Level: WARNING

## Description

Twilio couldn't create a new transcription because the value of `mediaUrl` is either malformed or uses an unsupported scheme.

### Possible causes

* The URL uses an unsupported scheme such as `ftp://`, `file://`, or `data://`.
* The URL is a relative path instead of an absolute URL.
* The URL is malformed and can't be parsed.

### Possible solutions

* Use a fully qualified URL that begins with `https://` or `s3://`.
* Make sure the URL is properly encoded and doesn't contain illegal characters.

#### Additional resources

* [Transcribe an external recording](https://www.twilio.com/docs/voice/api/batch-transcription-resource#transcribe-an-external-recording)
* [Create a transcription with a mediaUrl](https://www.twilio.com/docs/voice/api/batch-transcription-resource#create-a-transcription-with-a-media-url)