101101 Switching Protocols
The server is switching protocols as requested by the client via an Upgrade header.
304The resource has not been modified since the last request, so the client can use its cached copy.
The client sent a conditional request (with If-Modified-Since or If-None-Match headers) and the resource has not changed. The server responds without a body to save bandwidth.
No fix needed. Use the cached version of the resource. If you need a fresh copy, remove conditional headers from your request or add Cache-Control: no-cache.
101The server is switching protocols as requested by the client via an Upgrade header.
423The resource being accessed is locked and cannot be modified (WebDAV).
511The client needs to authenticate to gain network access, typically for captive portals.
404The server cannot find the requested resource. The URL may be incorrect or the resource may have been deleted.
305The requested resource must be accessed through the proxy specified in the Location header. This status code is deprecated.
406The server cannot produce a response matching the list of acceptable values defined in the request's Accept headers.