Error map

DST Root CA X3 expired (old clients fail) Old clients: certificate has expired — Let's Encrypt chain uses expired DST Root CA X3 (OpenSSL 1.0.x, Android < 7.1.1)

SSL / TLS · layer 2, Network

Open the full error page →

Centre: this error. First ring: errors it is linked with (7). 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.

1 · On your device 2 · Network 3 · Edge & web server 4 · Application & API 6 · Platform & cloud
DST Root CA X3 expired (old clients fail) — Old clients: certificate has expired — Let's Encrypt chain uses expired DST Root CA X3 (OpenSSL 1.0.x, Android < 7.1.1) (SSL / TLS)DST Root CA…ERR_CERT_DATE_INVALID — NET::ERR_CERT_DATE_INVALID (certificate expired) (JavaScript)ERR_CERT_DATE_INVAL…unable to get local issuer certificate — OpenSSL: error:num=20:unable to get local issuer certificate / SSL: CERTIFICATE_VERIFY_FAILED (SSL / TLS)unable to get local…DNS problem: NXDOMAIN looking up A — Certbot: Detail: DNS problem: NXDOMAIN looking up A for www.example.com - check that a DNS record exists for this domain (SSL / TLS)DNS problem: NXDOMA…SEC_ERROR_EXPIRED_CERTIFICATE — Firefox: Peer's Certificate has expired. Error code: SEC_ERROR_EXPIRED_CERTIFICATE (SSL / TLS)SEC_ERROR_EXPIRED_C…too many certificates already issued — Let's Encrypt: urn:ietf:params:acme:error:rateLimited :: too many certificates (5) already issued for this exact set of identifiers in the last 168 hours (SSL / TLS)too many certificat…The following certs could not be renewed — Certbot: Failed to renew certificate example.com with error — The following certs could not be renewed: /etc/letsencrypt/live/example.com/fullchain.pem (failure) (SSL / TLS)The following certs…Timeout during connect (likely firewall problem) — Let's Encrypt: Fetching http://example.com/.well-known/acme-challenge/token: Timeout during connect (likely firewall problem) (SSL / TLS)Timeout during conn…526 — Cloudflare Error 526: Invalid SSL Certificate (Cloudflare)526PKIX 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)QuotaExceededErrorERR_OSSL_EVP_UNSUPPORTED — Error: error:0308010C:digital envelope routines::unsupported (Node.js)ERR_OSSL_EVP_UNSUPP…no start line — OpenSSL: unable to load certificate / PEM routines:get_name:no start line (key values mismatch) (SSL / TLS)no start lineHandshakeException: CERTIFICATE_VERIFY_FAILED — Dart: HandshakeException: Handshake error in client (OS Error: CERTIFICATE_VERIFY_FAILED: unable to get local issuer certificate) (Flutter / Dart)HandshakeException:…sudo: unable to resolve host — sudo: unable to resolve host <hostname>: Name or service not known (Linux)sudo: unable to res…Temporary failure in name resolution — ping: google.com: Temporary failure in name resolution (Linux)Temporary failure i…523 — Cloudflare Error 523: Origin is unreachable (Cloudflare)523SSL_ERROR_BAD_CERT_DOMAIN — Firefox: Websites prove their identity via certificates — the certificate is only valid for other names. Error code: SSL_ERROR_BAD_CERT_DOMAIN (SSL / TLS)SSL_ERROR_BAD_CERT_…verify error:num=10: certificate has expired — OpenSSL: verify error:num=10:certificate has expired — notAfter=Jan 1 00:00:00 2025 GMT (SSL / TLS)verify error:num=10…AH01909: server certificate does NOT include an ID which matches the server name — Apache: [ssl:warn] AH01909: example.com:443:0 server certificate does NOT include an ID which matches the server name (SSL / TLS)AH01909: server cer…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…SSLCertificateFile: file does not exist — Apache: AH02240: Server should be SSL-aware but has no certificate configured / SSLCertificateFile: file '/etc/ssl/x.crt' does not exist or is empty (SSL / TLS)SSLCertificateFile:…Could not automatically find a matching server block — Certbot: Could not automatically find a matching server block for example.com. Set the `server_name` directive to use the Nginx installer (SSL / TLS)Could not automatic…Problem binding to port 80: Could not bind to IPv4 or IPv6 — Certbot: Problem binding to port 80: Could not bind to IPv4 or IPv6 (standalone authenticator) (SSL / TLS)Problem binding to …Invalid response from .well-known/acme-challenge: 404 — Certbot: Detail: Invalid response from http://example.com/.well-known/acme-challenge/abc: 404 (SSL / TLS)Invalid response fr…1020 — Cloudflare Error 1020: Access Denied (Cloudflare)1020ssh port 22 Connection timed out — ssh: connect to host x port 22: Connection timed out (Linux)ssh port 22 Connect…No route to host — connect: No route to host (EHOSTUNREACH) (Linux)No route to host

Directly related (7)

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.

unable to get local issuer certificateSSL / TLS

OpenSSL: error:num=20:unable to get local issuer certificate / SSL: CERTIFICATE_VERIFY_FAILED

The client could not build a chain from the server's certificate to a CA it trusts — the issuer is missing locally or the server…

DNS problem: NXDOMAIN looking up ASSL / TLS

Certbot: Detail: DNS problem: NXDOMAIN looking up A for www.example.com - check that a DNS record exists for this domain

Let's Encrypt could not resolve the domain you asked a certificate for; no A/AAAA record exists.

SEC_ERROR_EXPIRED_CERTIFICATESSL / TLS

Firefox: Peer's Certificate has expired. Error code: SEC_ERROR_EXPIRED_CERTIFICATE

Firefox found an expired certificate in the chain presented by the server.

too many certificates already issuedSSL / TLS

Let's Encrypt: urn:ietf:params:acme:error:rateLimited :: too many certificates (5) already issued for this exact set of identifiers in the last 168 hours

You hit a Let's Encrypt rate limit — too many certificates, failed validations or new orders in a period.

The following certs could not be renewedSSL / TLS

Certbot: Failed to renew certificate example.com with error — The following certs could not be renewed: /etc/letsencrypt/live/example.com/fullchain.pem (failure)

`certbot renew` failed for one or more certificates, so they will expire if you don't fix it.

Timeout during connect (likely firewall problem)SSL / TLS

Let's Encrypt: Fetching http://example.com/.well-known/acme-challenge/token: Timeout during connect (likely firewall problem)

The ACME validation server could not reach your server on port 80 within the timeout.

Two steps away (20)

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.

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.

ERR_OSSL_EVP_UNSUPPORTEDNode.js

Error: error:0308010C:digital envelope routines::unsupported

An old build tool (webpack 4, old react-scripts) uses a hash algorithm that OpenSSL 3 in Node 17+ disables.

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…

HandshakeException: CERTIFICATE_VERIFY_FAILEDFlutter / Dart

Dart: HandshakeException: Handshake error in client (OS Error: CERTIFICATE_VERIFY_FAILED: unable to get local issuer certificate)

The app refused the server's TLS certificate because it is self-signed, expired, missing intermediates, or the device clock/CA st…

sudo: unable to resolve hostLinux

sudo: unable to resolve host <hostname>: Name or service not known

The machine’s hostname isn’t in /etc/hosts (or DNS), so sudo prints this warning — usually after changing the hostname.

Temporary failure in name resolutionLinux

ping: google.com: Temporary failure in name resolution

The Linux host can’t resolve domain names — no working DNS server is configured or reachable.

523Cloudflare

Cloudflare Error 523: Origin is unreachable

Cloudflare can’t find a network route to your origin server — the DNS record points to a wrong/unroutable IP or the origin networ…

SSL_ERROR_BAD_CERT_DOMAINSSL / TLS

Firefox: Websites prove their identity via certificates — the certificate is only valid for other names. Error code: SSL_ERROR_BAD_CERT_DOMAIN

The certificate does not include the hostname you typed.

verify error:num=10: certificate has expiredSSL / TLS

OpenSSL: verify error:num=10:certificate has expired — notAfter=Jan 1 00:00:00 2025 GMT

OpenSSL's verification found a certificate in the chain whose validity period has ended.

AH01909: server certificate does NOT include an ID which matches the server nameSSL / TLS

Apache: [ssl:warn] AH01909: example.com:443:0 server certificate does NOT include an ID which matches the server name

Apache's SSL virtual host name does not match any name inside the certificate it loads.

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.

SSLCertificateFile: file does not existSSL / TLS

Apache: AH02240: Server should be SSL-aware but has no certificate configured / SSLCertificateFile: file '/etc/ssl/x.crt' does not exist or is empty

Apache cannot find the certificate or key file named in its configuration, or `SSLEngine on` is set without any certificate.

Could not automatically find a matching server blockSSL / TLS

Certbot: Could not automatically find a matching server block for example.com. Set the `server_name` directive to use the Nginx installer

Certbot's Nginx plugin could not find a `server` block whose `server_name` matches the domain you requested.

Problem binding to port 80: Could not bind to IPv4 or IPv6SSL / TLS

Certbot: Problem binding to port 80: Could not bind to IPv4 or IPv6 (standalone authenticator)

`certbot --standalone` needs to listen on port 80 for the HTTP-01 challenge but another process (Nginx, Apache) already holds it.

Invalid response from .well-known/acme-challenge: 404SSL / TLS

Certbot: Detail: Invalid response from http://example.com/.well-known/acme-challenge/abc: 404

Let's Encrypt reached your server but the challenge file was not found at `/.well-known/acme-challenge/`, so the web server retur…

1020Cloudflare

Cloudflare Error 1020: Access Denied

A Cloudflare firewall/WAF custom rule blocked the request — the visitor’s IP, country, user agent or request pattern matched a bl…

ssh port 22 Connection timed outLinux

ssh: connect to host x port 22: Connection timed out

SSH packets get no reply — a firewall/security group drops them, the server is off, or the IP is wrong.

No route to hostLinux

connect: No route to host (EHOSTUNREACH)

The destination host isn’t reachable — it’s down, on another subnet without routing, or a firewall rejects with “host unreachable…

Map another error

Popular: 500403400ORA-009331064Critical errorFileNotFoundException assemblyTypeError