Error guides

HTTP status codes & common website errors

Clear guides to what each error means and how to fix it, whether you are a visitor or you run the website.

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504 Gateway Timeout

A server acting as a gateway waited too long for a response from another server and gave up.
503 Service Unavailable

The server is online but temporarily cannot handle your request, usually because it is overloaded, restarting, or down for maintenance.
401 Unauthorized

A 401 Unauthorized error means the server received your request but it lacks valid authentication credentials for the resource.
Connection Timed Out (Chrome)

ERR_CONNECTION_TIMED_OUT means Chrome tried to open a connection to the website but the server did not respond in time, so the browser gave up.
Connection Timed Out

A connection timed out error means your device reached out to a server but no reply arrived within the allowed window, so it gave up waiting.
This Website Can't Be Reached

"This site can't be reached" means Chrome could not open a connection to the website.
Too Many Redirects

This error means a page sent your browser into a redirect loop, bouncing between addresses until the browser gave up.
SSL Certificate Error

An SSL certificate error means your browser could not establish a trusted, encrypted HTTPS connection, so it blocked the page and showed a warning such as "Your connection is not private".
DNS Server Not Responding

The page will not load, yet your Wi-Fi icon says you are online.
DNS Probe Finished (NXDOMAIN)

You click a link, and instead of the page you get a blunt This site can't be reached with the code DNS_PROBE_FINISHED_NXDOMAIN underneath.
502 Bad Gateway

You loaded a page and got 502 Bad Gateway instead.
500 Internal Server Error

You loaded a page and got a blank screen that just says 500 Internal Server Error.
403 Forbidden

You asked for a page and the server answered, but instead of the content it slammed the door: access to this resource is forbidden.
404 Not Found

You clicked a link, typed an address, or followed a search result, and instead of the page you wanted, the server hands back 404 Not Found.
400 Bad Request

You hit a page and instead of content you get a curt 400 Bad Request.
429 Too Many Requests

You loaded a page or hit an API and got slapped with 429 Too Many Requests.
Connection Refused

You typed an address, hit Enter, and Chrome bounced back instantly with This site can't be reached and ERR_CONNECTION_REFUSED.
SSL Protocol Error

You open an HTTPS page and Chrome stops you cold with This site can't provide a secure connection and the code ERR_SSL_PROTOCOL_ERROR.
DNS Name Not Resolved

ERR_NAME_NOT_RESOLVED is a Chrome and Chromium error that appears when the browser cannot translate a website's hostname into an IP address.
Connection Reset

ERR_CONNECTION_RESET appears in Chrome when a connection that had already started is forcibly closed before the page could finish loading.
SSL Version or Cipher Mismatch

ERR_SSL_VERSION_OR_CIPHER_MISMATCH is a Chrome error that fires when your browser and the website's server cannot agree on a single TLS protocol version or cipher suite to encrypt the connection.
Empty Response

ERR_EMPTY_RESPONSE is a Chrome error shown when the server accepted the connection but closed it without sending a single byte of HTTP response.
408 Request Timeout

A 408 Request Timeout means the server closed the connection because the client took too long to send the full request.

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HTTP status codes & common website errors

Find the cause and the fix

504 Gateway Timeout

503 Service Unavailable

401 Unauthorized

Connection Timed Out (Chrome)

Connection Timed Out

This Website Can't Be Reached

Too Many Redirects

SSL Certificate Error

DNS Server Not Responding

DNS Probe Finished (NXDOMAIN)

502 Bad Gateway

500 Internal Server Error

403 Forbidden

404 Not Found

400 Bad Request

429 Too Many Requests

Connection Refused

SSL Protocol Error

DNS Name Not Resolved

Connection Reset

SSL Version or Cipher Mismatch

Empty Response

408 Request Timeout

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