423 Locked

4xx Client error

The resource is locked.

On the wireHTTP/1.1 423 Locked
Code423
Is it an errorYes — this is an error
Category4xx Client error

The problem is on the request side; sending the same thing again will fail again.

How to read this

  • The first digit of a status code carries the meaning: 4 means the request, 5 means the server.
  • 404 means "not there"; 403 means "there, but not for you". Swapping them makes debugging slower.
  • Header names are case-insensitive — Content-Type and content-type are the same header.
  • Caching and CORS problems usually come down to one header line, visible in the browser’s network tab.

Frequently asked questions

Q. What does HTTP 423 Locked mean?

The resource is locked.

Q. What does 423 Locked look like on the wire?

It travels as HTTP/1.1 423 Locked

Q. Is 423 Locked an error?

Yes. A code starting with 4 blames the request; one starting with 5 blames the server.

Q. What group does 423 Locked belong to?

The 4xx client error group; the rest of that group is listed further down.

Same group

Reference docs