Transparent content negotiation caused a circular reference among variants.
Quick facts
When does it occur
Transparent content negotiation caused a circular reference among variants.
It belongs to the 5xx Server Error class of responses, defined in RFC2295#8.1.
Browse all codes in this class: 5xx Server Error
Common causes
Frequently asked questions
506 belongs to the 5xx Server Error class and is generally not cached for long; behavior is controlled by Cache-Control.
5xx Server Error: Transparent content negotiation caused a circular reference among variants.
Sources & standards
Updated 2026-08-18
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