Quick answer
HTTP status code 505 (HTTP Version Not Supported) means: The server does not support the HTTP version used in the request. Yes, a server error: the website failed to handle the request. Usually only the site owner or host can fix it.
Is it an error?
5xx Server errors
Yes, a server error: the website failed to handle the request. Usually only the site owner or host can fix it.
Common causes
- Client and server do not support the same protocol or version
If you are visiting the site
- Update your browser or app
If you run the website
- Review recent configuration changes (.htaccess, nginx/Apache rules)
Frequently asked questions
What does HTTP 505 mean?
HTTP status code 505 (HTTP Version Not Supported) means: The server does not support the HTTP version used in the request.
Is HTTP 505 an error?
Yes, a server error: the website failed to handle the request. Usually only the site owner or host can fix it.
How do I fix a 505 error?
If you are visiting the site: Update your browser or app. If you run the website: Review recent configuration changes (.htaccess, nginx/Apache rules).
5xx Server errors
HTTP 500 Internal Server ErrorThe server hit an unexpected error and could not complete the request.HTTP 501 Not ImplementedThe server does not support the function needed to complete the request.HTTP 502 Bad GatewayA gateway or proxy server received an invalid response from the server behind it.HTTP 503 Service UnavailableThe server is temporarily unable to handle the request because it is overloaded or under maintenance.HTTP 504 Gateway TimeoutA gateway or proxy server did not get a response in time from the server behind it.HTTP 507 Insufficient StorageThe server does not have enough storage space to complete the request.HTTP 508 Loop DetectedThe server detected an infinite loop while processing the request.HTTP 511 Network Authentication RequiredYou must sign in to the network (for example hotel, airport or public Wi-Fi) before you can use the internet.