501

Not Implemented

Description

The request method is not supported by the server and cannot be handled. The only methods that servers are required to support (and therefore that must not return this code) are GET and HEAD.

HTTP Status Codes Details

Status Code
501
Status Name
Not Implemented
Class
5xx
Common Usage
No

Common Scenarios

  • Server-side errors
  • Service unavailable

Handling Recommendations

  • Implement retry logic
  • Monitor server health

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Fact-checking completed

Verified by: Pavel Volkov
Created:
Last updated:
Information verified against official sources

Official Sources

Internet Engineering Task Force RFCs

Official HTTP status codes specification (RFC 7231)

Internet standards organization defining HTTP protocols

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Comprehensive HTTP status codes documentation

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Internet Assigned Numbers Authority

Official HTTP status code registry

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