| Previous | Next |
| WININET_E_DOWNLEVEL_SERVER | WININET_E_INVALID_HEADER |
WININET_E_INVALID_SERVER_RESPONSE
WININET_E_INVALID_SERVER_RESPONSE means that WinINet could not parse the server response as the protocol expected. For HTTP, this is a response-framing or syntax problem observed by the client, not an ordinary HTTP status code returned by the application.
What to collect
- The request method, URL, proxy route, and connection reuse state.
- Raw response bytes or a packet trace when permitted, with credentials redacted.
- Whether an intermediary injected a banner, authentication page, captive-portal page, or non-HTTP response.
Likely sources
An origin server, proxy, TLS-terminating gateway, or network interception device can all generate a malformed response. Test the same request through a direct route and through the configured proxy to locate the layer producing it.
Microsoft: WinINet error messages · Microsoft: HttpOpenRequest
Looking for a different code? Search another status or error code.