Error map

A TLS error caused the secure connection to fail Safari: Safari Can’t Open the Page — A TLS error caused the secure connection to fail

Browser · layer 1, On your device

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Centre: this error. First ring: errors it is linked with (8). Outer ring: what those are linked with. Colours show the layer of a request each error belongs to. Click any dot to re-centre the map on it; hover to follow its connections. The centre dot opens the error page.

A TLS error caused the secure connection to fail — Safari: Safari Can’t Open the Page — A TLS error caused the secure connection to fail (Browser)A TLS error…ERR_CERT_AUTHORITY_INVALID — NET::ERR_CERT_AUTHORITY_INVALID (Your connection is not private) (JavaScript)ERR_CERT_AUTHORITY_…ERR_CERT_DATE_INVALID — NET::ERR_CERT_DATE_INVALID (certificate expired) (JavaScript)ERR_CERT_DATE_INVAL…ERR_CONNECTION_CLOSED — Chrome: This site can’t be reached — example.com unexpectedly closed the connection. ERR_CONNECTION_CLOSED (Browser)ERR_CONNECTION_CLOS…ERR_SSL_VERSION_OR_CIPHER_MISMATCH — Chrome: This site can’t provide a secure connection — uses an unsupported protocol. ERR_SSL_VERSION_OR_CIPHER_MISMATCH (Browser)ERR_SSL_VERSION_OR_…NET::ERR_CERT_REVOKED — Chrome: Your connection is not private — NET::ERR_CERT_REVOKED (the certificate was revoked) (Browser)NET::ERR_CERT_REVOK…ERR_SSL_OBSOLETE_VERSION — Chrome: Connection not secure — ERR_SSL_OBSOLETE_VERSION (old TLS 1.0/1.1) (Browser)ERR_SSL_OBSOLETE_VE…SSL_ERROR_NO_CYPHER_OVERLAP — Firefox: Secure Connection Failed — SSL_ERROR_NO_CYPHER_OVERLAP (no common cipher) (Browser)SSL_ERROR_NO_CYPHER…Safari can’t find the server — Safari: Safari Can’t Open the Page because Safari can’t find the server (Browser)Safari can’t find t…CERTIFICATE_VERIFY_FAILED — SSL: CERTIFICATE_VERIFY_FAILED / unable to get local issuer certificate (API)CERTIFICATE_VERIFY_…PKIX path building failed — javax.net.ssl.SSLHandshakeException: PKIX path building failed: unable to find valid certification path to requested target (Java)PKIX path building …QuotaExceededError — QuotaExceededError: Failed to execute 'setItem' on 'Storage': Setting the value exceeded the quota (JavaScript)QuotaExceededError526 — Cloudflare Error 526: Invalid SSL Certificate (Cloudflare)526autoplay blocked — NotAllowedError: play() failed because the user didn't interact with the document first. (JavaScript)autoplay blockedclipboard write blocked — NotAllowedError: Failed to execute 'writeText' on 'Clipboard': Document is not focused. (JavaScript)clipboard write blo…525 — Cloudflare Error 525: SSL Handshake Failed (Cloudflare)525ERR_CONNECTION_RESET — ERR_CONNECTION_RESET: This site can’t be reached — The connection was reset (Browser)ERR_CONNECTION_RESETERR_NETWORK_CHANGED — Chrome: Your connection was interrupted — A network change was detected. ERR_NETWORK_CHANGED (Browser)ERR_NETWORK_CHANGEDERR_SSL_PROTOCOL_ERROR — ERR_SSL_PROTOCOL_ERROR (This site can't provide a secure connection) (JavaScript)ERR_SSL_PROTOCOL_ER…tlsv1 alert protocol version — SSL error: tlsv1 alert protocol version / unsupported protocol / no protocols available (API)tlsv1 alert protoco…Challenge failed for domain — Let’s Encrypt / Certbot: Challenge failed for domain example.com — Invalid response from http://example.com/.well-known/acme-challenge/x: 404 (SSL / TLS)Challenge failed fo…NET::ERR_CERT_COMMON_NAME_INVALID — NET::ERR_CERT_COMMON_NAME_INVALID: Your connection is not private (certificate is for a different domain) (SSL / TLS)NET::ERR_CERT_COMMO…no start line — OpenSSL: unable to load certificate / PEM routines:get_name:no start line (key values mismatch) (SSL / TLS)no start lineHSTS — Chrome: You cannot visit example.com right now because the website uses HSTS (NET::ERR_CERT_… no bypass) (Browser)HSTSSEC_ERROR_UNKNOWN_ISSUER — Firefox: Warning: Potential Security Risk Ahead — SEC_ERROR_UNKNOWN_ISSUER (certificate not trusted) (Browser)SEC_ERROR_UNKNOWN_I…The page isn’t redirecting properly — Firefox: The page isn’t redirecting properly — Firefox has detected that the server is redirecting the request in a way that will never complete (Browser)The page isn’t redi…Server not found — Firefox: Hmm. We’re having trouble finding that site. / Server not found (DNS_PROBE or NS_ERROR_UNKNOWN_HOST) (Browser)Server not foundENOTFOUND — Error: getaddrinfo ENOTFOUND host / Name or service not known (API)ENOTFOUND1000 — Cloudflare Error 1000: DNS points to prohibited IP (Cloudflare)1000DNS_PROBE_FINISHED_NXDOMAIN — Chrome: This site can’t be reached — server IP address could not be found. DNS_PROBE_FINISHED_NXDOMAIN (Browser)DNS_PROBE_FINISHED_…

Directly related (8)

ERR_CERT_AUTHORITY_INVALIDJavaScript

NET::ERR_CERT_AUTHORITY_INVALID (Your connection is not private)

The site’s certificate isn’t signed by a CA the browser trusts — self-signed, missing intermediates, or intercepted by a proxy.

ERR_CERT_DATE_INVALIDJavaScript

NET::ERR_CERT_DATE_INVALID (certificate expired)

The site’s certificate has expired (or isn’t valid yet) — or the device clock is wrong.

ERR_CONNECTION_CLOSEDBrowser

Chrome: This site can’t be reached — example.com unexpectedly closed the connection. ERR_CONNECTION_CLOSED

The server closed the connection before finishing the TLS handshake or sending a response — typical for HTTP/HTTPS port mix-ups,…

ERR_SSL_VERSION_OR_CIPHER_MISMATCHBrowser

Chrome: This site can’t provide a secure connection — uses an unsupported protocol. ERR_SSL_VERSION_OR_CIPHER_MISMATCH

The browser and the server could not agree on a TLS version or cipher — the server is too old or misconfigured, or the browser is.

NET::ERR_CERT_REVOKEDBrowser

Chrome: Your connection is not private — NET::ERR_CERT_REVOKED (the certificate was revoked)

The site’s TLS certificate has been revoked by the certificate authority, so browsers refuse to trust it.

ERR_SSL_OBSOLETE_VERSIONBrowser

Chrome: Connection not secure — ERR_SSL_OBSOLETE_VERSION (old TLS 1.0/1.1)

The server only supports an outdated TLS version that current browsers no longer allow.

SSL_ERROR_NO_CYPHER_OVERLAPBrowser

Firefox: Secure Connection Failed — SSL_ERROR_NO_CYPHER_OVERLAP (no common cipher)

Firefox and the server share no TLS cipher suite, so the secure handshake cannot even start.

Safari can’t find the serverBrowser

Safari: Safari Can’t Open the Page because Safari can’t find the server

Safari could not resolve the hostname — a typo, DNS trouble or no internet connection.

Two steps away (21)

CERTIFICATE_VERIFY_FAILEDAPI

SSL: CERTIFICATE_VERIFY_FAILED / unable to get local issuer certificate

The client couldn’t verify the server’s TLS certificate chain, so it refused the HTTPS connection.

PKIX path building failedJava

javax.net.ssl.SSLHandshakeException: PKIX path building failed: unable to find valid certification path to requested target

Java doesn’t trust the server’s certificate chain (self-signed, corporate proxy CA, or missing intermediate).

QuotaExceededErrorJavaScript

QuotaExceededError: Failed to execute 'setItem' on 'Storage': Setting the value exceeded the quota

localStorage/sessionStorage is full (about 5 MB per origin) or storage is disabled.

526Cloudflare

Cloudflare Error 526: Invalid SSL Certificate

With SSL mode Full (strict), the origin’s certificate is expired, self-signed, or doesn’t match the hostname.

autoplay blockedJavaScript

NotAllowedError: play() failed because the user didn't interact with the document first.

The browser blocked media autoplay with sound until the user interacts with the page.

clipboard write blockedJavaScript

NotAllowedError: Failed to execute 'writeText' on 'Clipboard': Document is not focused.

The Clipboard API refused to write — the page isn’t focused, there was no user gesture, or the context isn’t secure.

525Cloudflare

Cloudflare Error 525: SSL Handshake Failed

Cloudflare couldn’t complete a TLS handshake with your origin (SSL mode Full / Full strict).

ERR_CONNECTION_RESETBrowser

ERR_CONNECTION_RESET: This site can’t be reached — The connection was reset

The connection to the website was cut off mid-way — by the server, a firewall/antivirus, a VPN/proxy, or network equipment.

ERR_NETWORK_CHANGEDBrowser

Chrome: Your connection was interrupted — A network change was detected. ERR_NETWORK_CHANGED

The device switched networks (Wi-Fi to mobile data, VPN on/off, IP renewed) while the page was loading, so the browser aborted th…

ERR_SSL_PROTOCOL_ERRORJavaScript

ERR_SSL_PROTOCOL_ERROR (This site can't provide a secure connection)

The browser couldn’t negotiate TLS — the server sent an invalid response, often plain HTTP on the HTTPS port.

tlsv1 alert protocol versionAPI

SSL error: tlsv1 alert protocol version / unsupported protocol / no protocols available

The client and server couldn’t agree on a TLS version or cipher, so the HTTPS handshake failed before any HTTP was exchanged.

Challenge failed for domainSSL / TLS

Let’s Encrypt / Certbot: Challenge failed for domain example.com — Invalid response from http://example.com/.well-known/acme-challenge/x: 404

Let’s Encrypt couldn’t verify you control the domain — the HTTP-01 challenge file wasn’t served, or DNS points elsewhere.

NET::ERR_CERT_COMMON_NAME_INVALIDSSL / TLS

NET::ERR_CERT_COMMON_NAME_INVALID: Your connection is not private (certificate is for a different domain)

The certificate presented doesn’t include the hostname you visited — e.g. visiting www.example.com with a certificate only for ex…

no start lineSSL / TLS

OpenSSL: unable to load certificate / PEM routines:get_name:no start line (key values mismatch)

OpenSSL (or Nginx/Apache) couldn’t read the certificate or key — wrong file format, wrong file, or the key doesn’t match the cert…

HSTSBrowser

Chrome: You cannot visit example.com right now because the website uses HSTS (NET::ERR_CERT_… no bypass)

The site told browsers to use only valid HTTPS (HSTS), so Chrome hides the "Proceed anyway" link when its certificate has any pro…

SEC_ERROR_UNKNOWN_ISSUERBrowser

Firefox: Warning: Potential Security Risk Ahead — SEC_ERROR_UNKNOWN_ISSUER (certificate not trusted)

Firefox does not trust the authority that issued the site's certificate — a self-signed certificate, a missing intermediate, or a…

The page isn’t redirecting properlyBrowser

Firefox: The page isn’t redirecting properly — Firefox has detected that the server is redirecting the request in a way that will never complete

Firefox's wording for a redirect loop (Chrome calls it ERR_TOO_MANY_REDIRECTS).

Server not foundBrowser

Firefox: Hmm. We’re having trouble finding that site. / Server not found (DNS_PROBE or NS_ERROR_UNKNOWN_HOST)

Firefox could not resolve the website’s hostname to an IP address — a typo, a DNS problem or no internet.

ENOTFOUNDAPI

Error: getaddrinfo ENOTFOUND host / Name or service not known

DNS lookup for the hostname failed — the name is wrong, doesn’t exist, or this machine can’t resolve it.

1000Cloudflare

Cloudflare Error 1000: DNS points to prohibited IP

A proxied DNS record points at a Cloudflare IP address, creating a loop.

DNS_PROBE_FINISHED_NXDOMAINBrowser

Chrome: This site can’t be reached — server IP address could not be found. DNS_PROBE_FINISHED_NXDOMAIN

The DNS server answered that the domain name does not exist (NXDOMAIN) — a typo, an expired or unregistered domain, a missing DNS…