Yellorn Help Library

Field guides for the bugs you actually hit — every article maps a symptom in the Yellorn portal to a root cause and a copy-paste fix.

Debugging

Symptoms you can spot in the portal and how to fix them at the source.

Why your multipart/form-data request fails: CRLF, LF, and the \r\r\n trap
Multipart bodies require CRLF (\r\n) line endings between every header and boundary. Mixed CRLF/LF or doubled \r\r\n sequences cause parsers to reject the body silently. This guide explains why, shows how to spot the bug in Yellorn, and gives copy-paste fixes for cURL, fetch, Python requests, and Go.
Updated May 14, 2026

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