428
Precondition Required
Client ErrorThe origin server requires the request to be conditional to prevent lost updates.
Category: 4xx Client Errors Standard: RFC 6585
What is 428 Precondition Required?
HTTP 428 Precondition Required is a 4xx status code. The origin server requires the request to be conditional to prevent lost updates.
Client Request
Server
Request Rejected
Common Causes
The request was malformed or invalid
The client lacks permission or valid authentication
The requested resource or route does not exist
A precondition or content requirement was not met
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