1. General Results, most used to calculate the result A name "oxoooxo.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: 89449 (complete: 231048) A Good: All ip addresses are public addresses Warning: Only one ip address found: oxoooxo.com has only one ip address. Warning: Only one ip address found: www.oxoooxo.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: oxoooxo.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.oxoooxo.com has no ipv6 address. A Good: No asked Authoritative Name Server had a timeout A Good - only one version with Http-Status 200 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 (4 urls) http://oxoooxo.com/ 216.118.240.154 Url with incomplete Content-Type - header - missing charset http://www.oxoooxo.com/ 216.118.240.154 Url with incomplete Content-Type - header - missing charset http://oxoooxo.com/.well-known/acme-challenge/check-your-website-dot-server-daten-dot-de 216.118.240.154 Url with incomplete Content-Type - header - missing charset http://www.oxoooxo.com/.well-known/acme-challenge/check-your-website-dot-server-daten-dot-de 216.118.240.154 Url with incomplete Content-Type - header - missing charset H Fatal error: No https - result with http-status 200, no encryption 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. M http://oxoooxo.com/ 216.118.240.154 Misconfiguration - main pages should never send http status 400 - 499 Info: Checking the ip addresses of that domain name not exact one certificate found. So it's impossible to check if that domain requires Server Name Indication (SNI).: Domain oxoooxo.com, 1 ip addresses. Info: Checking the ip addresses of that domain name not exact one certificate found. So it's impossible to check if that domain requires Server Name Indication (SNI).: Domain www.oxoooxo.com, 1 ip addresses. 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.oxoooxo.com 2. Header-Checks U No https result with http status 2** or 4** (standard-check) found, no header checked. 3. DNS- and NameServer - Checks A Info:: 7 Root-climbing DNS Queries required to find all IPv4- and IPv6-Addresses of 2 Name Servers. A Info:: 7 Queries complete, 7 with IPv6, 0 with IPv4. A Good: All DNS Queries done via IPv6. Ok (4 - 8):: An average of 3.5 queries per domain name server required to find all ip addresses of all name servers. A Info:: 2 different Name Servers found: julissa.ns.cloudflare.com, lochlan.ns.cloudflare.com, 2 Name Servers included in Delegation: julissa.ns.cloudflare.com, lochlan.ns.cloudflare.com, 2 Name Servers included in 1 Zone definitions: julissa.ns.cloudflare.com, lochlan.ns.cloudflare.com, 1 Name Servers listed in SOA.Primary: julissa.ns.cloudflare.com. A Good: Only one SOA.Primary Name Server found.: julissa.ns.cloudflare.com. A Good: SOA.Primary Name Server included in the delegation set.: julissa.ns.cloudflare.com. A Good: Consistency 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. Ordered list of name servers: julissa.ns.cloudflare.com, lochlan.ns.cloudflare.com A Good: All Name Server Domain Names have a Public Suffix. A Good: All Name Server Domain Names ending with a Public Suffix have minimal one IPv4- or IPv6 address. A Good: All Name Server ip addresses are public. A Good: Minimal 2 different name servers (public suffix and public ip address) found: 2 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.: 2 Name Servers, 1 Top Level Domain: com Warning: All Name Servers have the same domain name. If there is a problem with that domain name (or with the name servers of that domain name), your domain may be affected. Better: Use Name Servers with different domain names / different top level domains.: Only one domain name used: cloudflare.com A Good: Name servers with different Country locations found: 2 Name Servers, 4 Countries: CA, CR, GB, US A Info: Ipv4-Subnet-list: 6 Name Servers, 3 different subnets (first Byte): 108., 162., 172., 3 different subnets (first two Bytes): 108.162., 162.159., 172.64., 6 different subnets (first three Bytes): 108.162.194., 108.162.195., 162.159.38., 162.159.44., 172.64.34., 172.64.35. A Good: Name Server IPv4-addresses from different subnet found: A Info: IPv6-Subnet-list: 6 Name Servers with IPv6, 3 different subnets (first block): 2606:, 2803:, 2a06:, 3 different subnets (first two blocks): 2606:4700:, 2803:f800:, 2a06:98c1:, 4 different subnets (first three blocks): 2606:4700:0050:, 2606:4700:0058:, 2803:f800:0050:, 2a06:98c1:0050:, 4 different subnets (first four blocks): 2606:4700:0050:0000:, 2606:4700:0058:0000:, 2803:f800:0050:0000:, 2a06:98c1:0050:0000: A Good: Name Server IPv6 addresses from different subnets found. A Good: Nameserver supports TCP connections: 12 good Nameserver A Good: Nameserver supports Echo Capitalization: 12 good Nameserver A Good: Nameserver supports EDNS with max. 512 Byte Udp payload, message is smaller: 12 good Nameserver A Good: Nameserver has passed 10 EDNS-Checks (OP100, FLAGS, V1, V1OP100, V1FLAGS, DNSSEC, V1DNSSEC, NSID, COOKIE, CLIENTSUBNET): 12 good Nameserver A Good: All SOA have the same Serial Number A Good: CAA entries found, creating certificate is limited: 0 issue "letsencrypt.org" is allowed to create certificates A Good: CAA entries found, creating certificate is limited: comodoca.com is allowed to create certificates A Good: CAA entries found, creating certificate is limited: digicert.com is allowed to create certificates A Good: CAA entries found, creating certificate is limited: letsencrypt.org is allowed to create certificates A Good: CAA entries found, creating certificate is limited: pki.goog is allowed to create certificates A Good: CAA entries found, creating certificate is limited: comodoca.com is allowed to create wildcard-certificates A Good: CAA entries found, creating certificate is limited: digicert.com is allowed to create wildcard-certificates A Good: CAA entries found, creating certificate is limited: letsencrypt.org is allowed to create wildcard-certificates A Good: CAA entries found, creating certificate is limited: pki.goog is allowed to create wildcard-certificates Warning: Unknown CAA found: 0 issue "letsencrypt.org" isn't defined. Unknown entry. May be wrong written, may be not longer valid. May be a missing entry in this tool. 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: All checked attribute values are enclosed in quotation marks (" or '). A Info: No img element found, no alt attribute checked 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: 100717 milliseconds, 100.717 seconds