HTTP 412 Precondition Failed
Client ErrorOne or more conditions in the request headers (If-Match, If-Unmodified-Since) evaluated to false on the server.
Common Causes
- ETag mismatch in If-Match header
- Resource modified since If-Unmodified-Since date
- Optimistic concurrency control rejection
How to Fix
- Fetch the latest ETag and retry with updated headers
- Re-read the resource and reapply changes
- Handle concurrent modification in application logic
Related Status Codes
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