1. General Results, most used to calculate the result A name "tplinkdns.com" is domain, public suffix is "com", top-level-domain-type is "generic", tld-manager is "VeriSign Global Registry Services" HSTS-Preload-Status: unknown. Domain never included in the Preload-list. Check https://hstspreload.org/ to learn some basics about the Google-Preload-List. X Fatal error: Nameserver isn't defined or has timeout X Fatal error: Nameserver doesn't support TCP connection: ns1.tplinkdns.com / 52.204.177.89: Fatal error - no NameServer IP-Address or connection. Details: One or more errors occurred. - Es konnte keine Verbindung hergestellt werden, da der Zielcomputer die Verbindung verweigerte 52.204.177.89:53 X Fatal error: Nameserver doesn't support TCP connection: ns2.tplinkdns.com / 54.87.217.253: Fatal error - no NameServer IP-Address or connection. Details: One or more errors occurred. - Es konnte keine Verbindung hergestellt werden, da der Zielcomputer die Verbindung verweigerte 54.87.217.253:53 X Fatal error: Nameserver doesn't support echo capitalization. That's critical if you want to create Letsencrypt certificates. Read https://tools.ietf.org/html/draft-vixie-dnsext-dns0x20-00 (2008). If a dns client asks "ExAmPlE.cOm", the name server must answer with the same name, not with "example.com". Creating Letsencrypt certificates isn't possible. Your name server provider must update the software.: ns1.tplinkdns.com / 52.204.177.89 X Fatal error: Nameserver doesn't support echo capitalization. That's critical if you want to create Letsencrypt certificates. Read https://tools.ietf.org/html/draft-vixie-dnsext-dns0x20-00 (2008). If a dns client asks "ExAmPlE.cOm", the name server must answer with the same name, not with "example.com". Creating Letsencrypt certificates isn't possible. Your name server provider must update the software.: ns2.tplinkdns.com / 54.87.217.253 2. DNS- and NameServer - Checks A A A Info:: 13 different Name Servers found: a.gtld-servers.net, b.gtld-servers.net, c.gtld-servers.net, d.gtld-servers.net, e.gtld-servers.net, f.gtld-servers.net, g.gtld-servers.net, h.gtld-servers.net, i.gtld-servers.net, j.gtld-servers.net, k.gtld-servers.net, l.gtld-servers.net, m.gtld-servers.net, 13 Name Servers included in Delegation: a.gtld-servers.net, b.gtld-servers.net, c.gtld-servers.net, d.gtld-servers.net, e.gtld-servers.net, f.gtld-servers.net, g.gtld-servers.net, h.gtld-servers.net, i.gtld-servers.net, j.gtld-servers.net, k.gtld-servers.net, l.gtld-servers.net, m.gtld-servers.net, 13 Name Servers included in 1 Zone definitions: a.gtld-servers.net, b.gtld-servers.net, c.gtld-servers.net, d.gtld-servers.net, e.gtld-servers.net, f.gtld-servers.net, g.gtld-servers.net, h.gtld-servers.net, i.gtld-servers.net, j.gtld-servers.net, k.gtld-servers.net, l.gtld-servers.net, m.gtld-servers.net, 1 Name Servers listed in SOA.Primary: a.gtld-servers.net. A Good: Only one SOA.Primary Name Server found.: a.gtld-servers.net. A Good: SOA.Primary Name Server included in the delegation set.: a.gtld-servers.net. A Good: All Name Server Domain Names have a Public Suffix. Error: Name Server Domain Names with Public Suffix and without ip address found.: 13 Name Servers without ipv4 and ipv6: a.gtld-servers.net, b.gtld-servers.net, c.gtld-servers.net, d.gtld-servers.net, e.gtld-servers.net, f.gtld-servers.net, g.gtld-servers.net, h.gtld-servers.net, i.gtld-servers.net, j.gtld-servers.net, k.gtld-servers.net, l.gtld-servers.net, m.gtld-servers.net 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: gtld-servers.net A X Fatal error: Nameserver doesn't support EDNS with max. 512 Byte Udp payload or sends more then 512 Bytes: ns1.tplinkdns.com X Fatal error: Nameserver doesn't support EDNS with max. 512 Byte Udp payload or sends more then 512 Bytes: ns2.tplinkdns.com Nameserver doesn't pass all EDNS-Checks: ns1.tplinkdns.com / 52.204.177.89: OP100: no result. FLAGS: no result. V1: no result. V1OP100: no result. V1FLAGS: no result. DNSSEC: no result. V1DNSSEC: no result. NSID: no result. COOKIE: no result. CLIENTSUBNET: no result. Nameserver doesn't pass all EDNS-Checks: ns2.tplinkdns.com / 54.87.217.253: OP100: no result. FLAGS: no result. V1: no result. V1OP100: no result. V1FLAGS: no result. DNSSEC: no result. V1DNSSEC: no result. NSID: no result. COOKIE: no result. CLIENTSUBNET: no result. A Good: All SOA have the same Serial Number 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. 3. Content- and Performance-critical Checks 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: 44206 milliseconds, 44.206 seconds