423 Locked (RFC 4918, WebDAV) means the source or destination resource of a method is locked and the request did not include a matching lock token. WebDAV clients lock files while editing them so that other users cannot overwrite their changes.
The response body should contain a precondition element such as lock-token-submitted that lists the URL of the locked resource. The client can wait until the lock is released or expires, or, if it owns the lock, send the lock token in an If header.
Example response
HTTP/1.1 423 Locked
Date: Fri, 06 Nov 2026 10:15:32 GMT
Content-Type: application/xml; charset=utf-8
Content-Length: 166
<?xml version="1.0" encoding="utf-8"?>
<d:error xmlns:d="DAV:">
<d:lock-token-submitted>
<d:href>/docs/plan.docx</d:href>
</d:lock-token-submitted>
</d:error> SEO and redirect checking
No SEO impact: locks only affect WebDAV methods such as PUT, MOVE and DELETE, which crawlers never send.
Common causes and use cases
- Another user has the document open for editing on a WebDAV share.
- A stale lock remained after a client crashed. It expires after its timeout, or an administrator can remove it.
- A sync client tries to update a file that another client has locked.