Discord error 50046: Invalid file uploaded

Discord could not accept the file you uploaded because it is malformed for its purpose, not because of its size. For images used as emoji, avatars, banners, icons and stickers, Discord must be able to decode the image; a corrupt PNG, a file with the wrong extension, an unsupported format (for example WebP where only PNG/JPEG/GIF are accepted for that field, or a non-APNG/Lottie sticker), or a data URI with the wrong MIME prefix all produce 50046.

For message attachments, the multipart body must be well-formed: each file part named files[n] with a filename, and any attachments metadata in payload_json referencing the right index. A zero-byte file, a part with no filename, or a mismatch between the declared and actual file can also trigger this.

{
  "message": "Invalid file uploaded",
  "code": 50046
}

Validate and normalize media in your pipeline (decode, re-encode to a known-good format, check dimensions and size) before it reaches Discord. Use your library's attachment helpers, which build the multipart body correctly, rather than constructing it by hand.

Media validation is cheapest at ingestion: decode, re-encode, and store a known-good normalized copy, then uploads to Discord never fail on format. The per-field format rules and size caps are on the Discord limits page; if your multipart body itself is malformed rather than the file, the error is 50035 naming the part.