1. General Results, most used to calculate the result A name "factuminv.com" is domain, public suffix is ".com", top-level-domain is ".com", top-level-domain-type is "generic", tld-manager is "VeriSign Global Registry Services", num .com-domains preloaded: 83852 (complete: 216710) A Good: All ip addresses are public addresses Warning: Only one ip address found: factuminv.com has only one ip address. Warning: Only one ip address found: www.factuminv.com has only one ip address. Warning: No ipv6 address found. Ipv6 is the future with a lot of new features. So every domain name should have an ipv6 address. See https://en.wikipedia.org/wiki/IPv6: factuminv.com has no ipv6 address. Warning: No ipv6 address found. Ipv6 is the future with a lot of new features. So every domain name should have an ipv6 address. See https://en.wikipedia.org/wiki/IPv6: www.factuminv.com has no ipv6 address. A Good: No cookie sent via http. HSTS-Preload-Status: unknown. Domain never included in the Preload-list. Check https://hstspreload.org/ to learn some basics about the Google-Preload-List. A Good: Some urls with http status 200/404 have a complete Content-Type header (MediaType / MediaSubType + correct charset):0 complete Content-Type - header (9 urls) http://factuminv.com/ 50.31.174.98 Url with incomplete Content-Type - header - missing charset http://www.factuminv.com/ 50.31.174.98 Url with incomplete Content-Type - header - missing charset https://factuminv.com/ 50.31.174.98 Url with incomplete Content-Type - header - missing charset https://www.factuminv.com/ 50.31.174.98 Url with incomplete Content-Type - header - missing charset http://factuminv.com/.well-known/acme-challenge/check-your-website-dot-server-daten-dot-de 50.31.174.98 Url with incomplete Content-Type - header - missing charset http://www.factuminv.com/.well-known/acme-challenge/check-your-website-dot-server-daten-dot-de 50.31.174.98 Url with incomplete Content-Type - header - missing charset http://www.factuminv.com/.well-known/acme-challenge/check-your-website-dot-server-daten-dot-de 50.31.174.103 Url with incomplete Content-Type - header - missing charset https://50.31.174.98/ 50.31.174.98 Url with incomplete Content-Type - header - missing charset https://50.31.174.103/ 50.31.174.103 Url with incomplete Content-Type - header - missing charset A http://www.factuminv.com/ 50.31.174.103 https://www.factuminv.com/ Correct redirect http - https with the same domain name B https://factuminv.com/ 50.31.174.98 Missing HSTS-Header B https://www.factuminv.com/ 50.31.174.103 Missing HSTS-Header B https://www.factuminv.com/ 50.31.174.98 Missing HSTS-Header C Error - no preferred version www or non-www. Select one version as preferred version, then add a redirect https + not-preferred version to https + preferred version. Perhaps in your port 443 vHost something like "RewriteEngine on" + "RewriteCond %{SERVER_NAME} = example.com" + "ReWriteRule ^ https://www.example.com%{REQUEST_URI} [END,QSA,R=permanent]" (three rows, without the "). That should create a redirect https + example.com ⇒ https + www.example.com. Or switch both values to use the non-www version as your preferred version. C Error - more then one version with Http-Status 200. After all redirects, all users (and search engines) should see the same https url: Non-www or www, but not both with http status 200. H Fatal error: http result with http-status 200, no encryption. Add a redirect http ⇒ https, so every connection is secure. Perhaps in your port 80 vHost something like "RewriteEngine on" + "RewriteRule ^ https://%{SERVER_NAME}%{REQUEST_URI} [END,QSA,R=permanent]" (two rows, without the "). Don't add this in your port 443 vHost, that would create a loop. J https://factuminv.com/ 50.31.174.98 Fatal: Control Panel error message. Ask your hoster. There is a cPanel-Redirect to the SORRY-page /cgi-sys/defaultwebpage.cgi with additional instructions. J https://www.factuminv.com/ 50.31.174.98 Fatal: Control Panel error message. Ask your hoster. There is a cPanel-Redirect to the SORRY-page /cgi-sys/defaultwebpage.cgi with additional instructions. J https://50.31.174.98/ 50.31.174.98 Fatal: Control Panel error message. Ask your hoster. There is a cPanel-Redirect to the SORRY-page /cgi-sys/defaultwebpage.cgi with additional instructions. J https://50.31.174.103/ 50.31.174.103 Fatal: Control Panel error message. Ask your hoster. There is a cPanel-Redirect to the SORRY-page /cgi-sys/defaultwebpage.cgi with additional instructions. K http://www.factuminv.com/ 50.31.174.98, Status 200 http://www.factuminv.com/ 50.31.174.103, Status 301 Configuration problem - different ip addresses with different status K https://www.factuminv.com/ 50.31.174.98, Status 200 https://www.factuminv.com/ 50.31.174.103, Status 301 Configuration problem - different ip addresses with different status N https://factuminv.com/ 50.31.174.98 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N https://www.factuminv.com/ 50.31.174.98 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N https://50.31.174.98/ 50.31.174.98 Error - Certificate isn't trusted, RemoteCertificateNameMismatch N https://50.31.174.103/ 50.31.174.103 Error - Certificate isn't trusted, RemoteCertificateNameMismatch, RemoteCertificateChainErrors O factuminv.com / 50.31.174.98 / 993 Old connection: Ssl3 is insecure and must be disabled. O factuminv.com / 50.31.174.98 / 995 Old connection: Ssl3 is insecure and must be disabled. O www.factuminv.com / 50.31.174.98 / 995 Old connection: Ssl3 is insecure and must be disabled. O www.factuminv.com / 50.31.174.98 / 993 Old connection: Ssl3 is insecure and must be disabled. O factuminv.com / 50.31.174.98 / 465 ECDHE-RSA-RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O factuminv.com / 50.31.174.98 / 465 RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O factuminv.com / 50.31.174.98 / 587 RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O factuminv.com / 50.31.174.98 / 587 ECDHE-RSA-RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O factuminv.com / 50.31.174.98 / 993 ECDHE-RSA-RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O factuminv.com / 50.31.174.98 / 995 ECDHE-RSA-RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O factuminv.com / 50.31.174.98 / 993 RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O factuminv.com / 50.31.174.98 / 995 RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O factuminv.com / 50.31.174.98 / 465 RC4-MD5 Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O factuminv.com / 50.31.174.98 / 587 RC4-MD5 Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O factuminv.com / 50.31.174.98 / 993 RC4-MD5 Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O factuminv.com / 50.31.174.98 / 995 RC4-MD5 Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O www.factuminv.com / 50.31.174.98 / 995 RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O www.factuminv.com / 50.31.174.98 / 995 RC4-MD5 Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O www.factuminv.com / 50.31.174.98 / 587 RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O www.factuminv.com / 50.31.174.98 / 587 RC4-MD5 Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O www.factuminv.com / 50.31.174.98 / 993 RC4-MD5 Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O www.factuminv.com / 50.31.174.98 / 465 RC4-MD5 Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O www.factuminv.com / 50.31.174.98 / 465 RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O www.factuminv.com / 50.31.174.98 / 993 RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O www.factuminv.com / 50.31.174.98 / 587 ECDHE-RSA-RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O www.factuminv.com / 50.31.174.98 / 995 ECDHE-RSA-RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O www.factuminv.com / 50.31.174.98 / 465 ECDHE-RSA-RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O www.factuminv.com / 50.31.174.98 / 993 ECDHE-RSA-RC4-SHA Old connection: Insecure Cipher Suite found. Such active Cipher Suites allow downgrades. Remove all insecure Cipher Suites O factuminv.com / 50.31.174.98 / 995 AECDH-AES256-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O factuminv.com / 50.31.174.98 / 993 AECDH-AES256-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O factuminv.com / 50.31.174.98 / 993 AECDH-DES-CBC3-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O factuminv.com / 50.31.174.98 / 995 AECDH-DES-CBC3-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O factuminv.com / 50.31.174.98 / 993 AECDH-AES128-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O factuminv.com / 50.31.174.98 / 993 AECDH-RC4-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O factuminv.com / 50.31.174.98 / 995 AECDH-AES128-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O factuminv.com / 50.31.174.98 / 995 AECDH-RC4-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O www.factuminv.com / 50.31.174.98 / 995 AECDH-RC4-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O www.factuminv.com / 50.31.174.98 / 995 AECDH-DES-CBC3-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O www.factuminv.com / 50.31.174.98 / 993 AECDH-AES256-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O www.factuminv.com / 50.31.174.98 / 993 AECDH-AES128-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O www.factuminv.com / 50.31.174.98 / 995 AECDH-AES128-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O www.factuminv.com / 50.31.174.98 / 995 AECDH-AES256-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O www.factuminv.com / 50.31.174.98 / 993 AECDH-RC4-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O www.factuminv.com / 50.31.174.98 / 993 AECDH-DES-CBC3-SHA Old connection: Insecure Cipher Suite without Authentication found (_anon_ = Anonymous in the IANA-Name). Remove these Cipher Suites. O factuminv.com / 50.31.174.98 / 465 Old connection: Cipher Suites without Forward Secrecy (FS) found. Remove all of these Cipher Suites, use only Cipher Suites with Forward Secrecy: Starting with ECDHE- or DHE - the last "E" says: "ephemeral". Or use Tls.1.3, then all Cipher Suites use FS. 13 Cipher Suites without Forward Secrecy found O factuminv.com / 50.31.174.98 / 587 Old connection: Cipher Suites without Forward Secrecy (FS) found. Remove all of these Cipher Suites, use only Cipher Suites with Forward Secrecy: Starting with ECDHE- or DHE - the last "E" says: "ephemeral". Or use Tls.1.3, then all Cipher Suites use FS. 13 Cipher Suites without Forward Secrecy found O factuminv.com / 50.31.174.98 / 993 Old connection: Cipher Suites without Forward Secrecy (FS) found. Remove all of these Cipher Suites, use only Cipher Suites with Forward Secrecy: Starting with ECDHE- or DHE - the last "E" says: "ephemeral". Or use Tls.1.3, then all Cipher Suites use FS. 17 Cipher Suites without Forward Secrecy found O factuminv.com / 50.31.174.98 / 995 Old connection: Cipher Suites without Forward Secrecy (FS) found. Remove all of these Cipher Suites, use only Cipher Suites with Forward Secrecy: Starting with ECDHE- or DHE - the last "E" says: "ephemeral". Or use Tls.1.3, then all Cipher Suites use FS. 17 Cipher Suites without Forward Secrecy found O www.factuminv.com / 50.31.174.98 / 465 Old connection: Cipher Suites without Forward Secrecy (FS) found. Remove all of these Cipher Suites, use only Cipher Suites with Forward Secrecy: Starting with ECDHE- or DHE - the last "E" says: "ephemeral". Or use Tls.1.3, then all Cipher Suites use FS. 13 Cipher Suites without Forward Secrecy found O www.factuminv.com / 50.31.174.98 / 587 Old connection: Cipher Suites without Forward Secrecy (FS) found. Remove all of these Cipher Suites, use only Cipher Suites with Forward Secrecy: Starting with ECDHE- or DHE - the last "E" says: "ephemeral". Or use Tls.1.3, then all Cipher Suites use FS. 13 Cipher Suites without Forward Secrecy found O www.factuminv.com / 50.31.174.98 / 993 Old connection: Cipher Suites without Forward Secrecy (FS) found. Remove all of these Cipher Suites, use only Cipher Suites with Forward Secrecy: Starting with ECDHE- or DHE - the last "E" says: "ephemeral". Or use Tls.1.3, then all Cipher Suites use FS. 17 Cipher Suites without Forward Secrecy found O www.factuminv.com / 50.31.174.98 / 995 Old connection: Cipher Suites without Forward Secrecy (FS) found. Remove all of these Cipher Suites, use only Cipher Suites with Forward Secrecy: Starting with ECDHE- or DHE - the last "E" says: "ephemeral". Or use Tls.1.3, then all Cipher Suites use FS. 17 Cipher Suites without Forward Secrecy found X Fatal error: Nameserver isn't defined or has timeout X Fatal error: Nameserver doesn't support TCP connection: no-dyn-updates.san.yahoo.com: Timeout Info: Checking all ip addresses of that domain without sending the hostname only one certificate found. Checking all ip addresses and sending the hostname only one certificate found. Both certificates are the same. So that domain doesn't require Server Name Indication (SNI), it's the primary certificate of that set of ip addresses.: Domain factuminv.com, 1 ip addresses, 1 different http results. Info: Checking all ip addresses of that domain without sending the hostname only one certificate found. Checking all ip addresses and sending the hostname only one certificate found. Both certificates are the same. So that domain doesn't require Server Name Indication (SNI), it's the primary certificate of that set of ip addresses.: Domain www.factuminv.com, 1 ip addresses, 1 different http results. B No _mta-sts TXT record found (mta-sts: Mail Transfer Agent Strict Transport Security - see RFC 8461). Read the result of server-daten.de (Url-Checks, Comments, Connections and DomainServiceRecords) to see a complete definition. Domainname: _mta-sts.factuminv.com 2. Header-Checks (alpha, started 2022-10-23, may be buggy / incomplete) F factuminv.com 50.31.174.98 Content-Security-Policy Critical: Missing Header: F factuminv.com 50.31.174.98 X-Content-Type-Options Critical: Missing Header: F factuminv.com 50.31.174.98 Referrer-Policy Critical: Missing Header: F factuminv.com 50.31.174.98 Permissions-Policy Critical: Missing Header: F www.factuminv.com 50.31.174.98 Content-Security-Policy Critical: Missing Header: F www.factuminv.com 50.31.174.98 X-Content-Type-Options Critical: Missing Header: F www.factuminv.com 50.31.174.98 Referrer-Policy Critical: Missing Header: F www.factuminv.com 50.31.174.98 Permissions-Policy Critical: Missing Header: 3. DNS- and NameServer - Checks A Info:: 13 Root-climbing DNS Queries required to find all IPv4- and IPv6-Addresses of 4 Name Servers. A Info:: 13 Queries complete, 13 with IPv6, 0 with IPv4. A Good: All DNS Queries done via IPv6. Ok (4 - 8):: An average of 3.3 queries per domain name server required to find all ip addresses of all name servers. A Info:: 5 different Name Servers found: no-dyn-updates.san.yahoo.com, ns7112.banahosting.com, ns7113.banahosting.com, yns1.yahoo.com, yns2.yahoo.com, 4 Name Servers included in Delegation: ns7112.banahosting.com, ns7113.banahosting.com, yns1.yahoo.com, yns2.yahoo.com, 4 Name Servers included in 3 Zone definitions: ns7112.banahosting.com, ns7113.banahosting.com, yns1.yahoo.com, yns2.yahoo.com, 2 Name Servers listed in SOA.Primary: no-dyn-updates.san.yahoo.com, ns7112.banahosting.com. Error: Different SOA.Primary Name Servers found, different SOA Definitions.: no-dyn-updates.san.yahoo.com,ns7112.banahosting.com. Error: SOA.Primary Name Server not included in the delegation set.: no-dyn-updates.san.yahoo.com,ns7112.banahosting.com. X Fatal: Inconsistency between delegation and zone. The set of NS records served by the authoritative name servers must match those proposed for the delegation in the parent zone. Read https://www.iana.org/help/nameserver-requirements and send it to your Name Server Hoster.: ns7112.banahosting.com (50.31.174.99): Delegation: ns7112.banahosting.com, ns7113.banahosting.com, yns1.yahoo.com, yns2.yahoo.com, Zone: ns7112.banahosting.com, ns7113.banahosting.com. Name Servers defined in Delegation, missing in Zone: yns1.yahoo.com, yns2.yahoo.com. X Fatal: Inconsistency between delegation and zone. The set of NS records served by the authoritative name servers must match those proposed for the delegation in the parent zone. Read https://www.iana.org/help/nameserver-requirements and send it to your Name Server Hoster.: ns7113.banahosting.com (50.31.174.100): Delegation: ns7112.banahosting.com, ns7113.banahosting.com, yns1.yahoo.com, yns2.yahoo.com, Zone: ns7112.banahosting.com, ns7113.banahosting.com. Name Servers defined in Delegation, missing in Zone: yns1.yahoo.com, yns2.yahoo.com. X Fatal: Inconsistency between delegation and zone. The set of NS records served by the authoritative name servers must match those proposed for the delegation in the parent zone. Read https://www.iana.org/help/nameserver-requirements and send it to your Name Server Hoster.: yns1.yahoo.com (67.195.1.92): Delegation: ns7112.banahosting.com, ns7113.banahosting.com, yns1.yahoo.com, yns2.yahoo.com, Zone: yns1.yahoo.com, yns2.yahoo.com. Name Servers defined in Delegation, missing in Zone: ns7112.banahosting.com, ns7113.banahosting.com. X Fatal: Inconsistency between delegation and zone. The set of NS records served by the authoritative name servers must match those proposed for the delegation in the parent zone. Read https://www.iana.org/help/nameserver-requirements and send it to your Name Server Hoster.: yns2.yahoo.com (98.139.247.192): Delegation: ns7112.banahosting.com, ns7113.banahosting.com, yns1.yahoo.com, yns2.yahoo.com, Zone: yns1.yahoo.com, yns2.yahoo.com. Name Servers defined in Delegation, missing in Zone: ns7112.banahosting.com, ns7113.banahosting.com. A Good: All Name Server Domain Names have a Public Suffix. Error: Name Server Domain Names with Public Suffix and without ip address found.: 1 Name Servers without ipv4 and ipv6: 1 A Good: Minimal 2 different name servers (public suffix and public ip address) found: 4 different Name Servers found Warning: No Name Server IPv6 address found. IPv6 is the future, so your name servers should be visible via IPv6.: 4 different Name Servers found Warning: All Name Servers have the same Top Level Domain / Public Suffix. If there is a problem with that Top Level Domain, your domain may be affected. Better: Use Name Servers with different top level domains.: 4 Name Servers, 1 Top Level Domain: com A Good: Name Servers with different domain names found.: 2 different Domains found Warning: All Name Servers from the same Country / IP location.: 4 Name Servers, 1 Countries: US A Info: Ipv4-Subnet-list: 4 Name Servers, 3 different subnets (first Byte): 50., 67., 98., 3 different subnets (first two Bytes): 50.31., 67.195., 98.139., 3 different subnets (first three Bytes): 50.31.174., 67.195.1., 98.139.247. A Good: Name Server IPv4-addresses from different subnet found: A Info: Nameserver mit different domain names found. May be a problem with DNS-Updates X Nameserver Timeout checking EDNS512: ns7113.banahosting.com / 50.31.174.100 Nameserver doesn't pass all EDNS-Checks: no-dyn-updates.san.yahoo.com: OP100: fatal timeout. FLAGS: fatal timeout. V1: fatal timeout. V1OP100: fatal timeout. V1FLAGS: fatal timeout. DNSSEC: fatal timeout. V1DNSSEC: fatal timeout. NSID: fatal timeout. COOKIE: fatal timeout. CLIENTSUBNET: fatal timeout. X Fatal error: Nameservers with different SOA Serial Numbers Warning: No CAA entry with issue/issuewild found, every CAA can create a certificate. Read https://en.wikipedia.org/wiki/DNS_Certification_Authority_Authorization to learn some basics about the idea of CAA. Your name server must support such an entry. Not all dns providers support CAA entries. 4. Content- and Performance-critical Checks A Good: All checks /.well-known/acme-challenge/random-filename without redirects answer with the expected http status 404 - Not Found. Creating a Letsencrypt certificate via http-01 challenge should work. If it doesn't work: Check your vHost configuration (apachectl -S, httpd -S, nginx -T). Every combination of port and ServerName / ServerAlias (Apache) or Server (Nginx) must be unique. Merge duplicated entries in one vHost. If you use an IIS, extensionless files must be allowed in the /.well-known/acme-challenge subdirectory. Create a web.config in that directory. Content: <configuration><system.webServer><staticContent><mimeMap fileExtension="." mimeType="text/plain" /></staticContent></system.webServer></configuration>. If you have a redirect http ⇒ https, that's ok, Letsencrypt follows such redirects to port 80 / 443 (same or other server). There must be a certificate. But the certificate may be expired, self signed or with a not matching domain name. Checking the validation file Letsencrypt ignores such certificate errors. Trouble creating a certificate? Use https://community.letsencrypt.org/ to ask. A Good: No https + http status 200 with inline CSS / JavaScript found A Good: Every https result with status 200 has a minified Html-Content with a quota lower then 110 %. A Good: Every https connection via port 443 supports the http/2 protocol via ALPN. Warning: Images with a missing or too short Cache-Control header found. Browsers should cache and re-use these files. 4 image files without Cache-Control-Header, 0 with Cache-Control, but no max-age, 0 with Cache-Control max-age too short (minimum 7 days), 0 with Cache-Control long enough, 4 complete. A Good: All checked attribute values are enclosed in quotation marks (" or '). A Good: Some img-elements have a valid alt-attribute.: 4 img-elements found, 2 img-elements with correct alt-attributes (defined, not an empty value). Wrong: img-elements without alt-attribute or empty alt-attribute found. The alt-attribute ("alternative") is required and should describe the img. So Screenreader and search engines are able to use these informations.: 2 img-elements without alt-attribute, 0 img-elements with empty alt-attribute found. A Good: Domainname is not on the "Specially Designated Nationals And Blocked Persons List" (SDN). That's an US-list of individuals and companies owned or controlled by, or acting for or on behalf of, targeted countries. It also lists individuals, groups, and entities, such as terrorists and narcotics traffickers designated under programs that are not country-specific. Collectively, such individuals and companies are called "Specially Designated Nationals" or "SDNs." Their assets are blocked and U.S. persons are generally prohibited from dealing with them. So if a domain name is on that list, it's impossible to create a Letsencrypt certificate with that domain name. Check the list manual - https://www.treasury.gov/resource-center/sanctions/sdn-list/pages/default.aspx A Duration: 2208274 milliseconds, 2208.274 seconds