1. General Results, most used to calculate the result A name "18.214.25.211" is ipv4 address, public suffix is not defined A good: All ip addresses are public addresses A good: destination is https A good - only one version with Http-Status 200 A Good: All urls with http status 200/404 have a complete Content-Type header (MediaType / MediaSubType + correct charset) B https://18.214.25.211/ 18.214.25.211 Missing HSTS-Header I https://18.214.25.211/ 18.214.25.211 Content problems or problems with resources included - http links, files doesn't exist, different Content-Type definitions. Check the Html-Content - Part. N https://18.214.25.211/ 18.214.25.211 Error - Certificate isn't trusted, RemoteCertificateChainErrors N https://18.214.25.211/ 18.214.25.211 Error - Certificate isn't trusted, RemoteCertificateNameMismatch, RemoteCertificateChainErrors V http://18.214.25.211/ 18.214.25.211 connect failure - perhaps firewall V http://18.214.25.211/.well-known/acme-challenge/check-your-website-dot-server-daten-dot-de 18.214.25.211 connect failure - perhaps firewall 2. DNS- and NameServer - Checks 3. Content- and Performance-critical Checks http://18.214.25.211/.well-known/acme-challenge/check-your-website-dot-server-daten-dot-de 18.214.25.211 Fatal: Check of /.well-known/acme-challenge/random-filename is blocked, http connection error. Creating a Letsencrypt certificate via http-01 challenge can't work. You need a running webserver (http) and an open port 80. If it's a home server + ipv4, perhaps a correct port forwarding port 80 extern ⇒ working port intern is required. Port 80 / http can redirect to another domain port 80 or port 443, but not other ports. If it's a home server, perhaps your ISP blocks port 80. Then you may use the dns-01 challenge. Trouble creating a certificate? Use https://community.letsencrypt.org/ to ask. A Good: No https + http status 200 with inline CSS / JavaScript found https://18.214.25.211/ 18.214.25.211 Warning: Https result with status 200 found, Html-Content is too big. Should be max. 110 %. May contain inline CSS / JavaScript, too much comments or white space. Re-used ressources - create files with a long Cache-Control max-age header. Remove comments and white space. https://18.214.25.211/ 18.214.25.211 Warning: Https result with status 200 found, Html-Content is too big. Should be max. 110 %. May contain inline CSS / JavaScript, too much comments or white space. Re-used ressources - create files with a long Cache-Control max-age header. Remove comments and white space. https://18.214.25.211/ 18.214.25.211 Warning: Https connections (Standard Port 443) found without support of the http/2 protocol via ALPN. Http/2 is the new Http-Version (old: http 1.1) with some important new features. Update your server software so http/2 is available. Only one TCP-connection per Server (that's a performance boost), Header-Compression and Server Pushs are available. Domain Sharding and Inline-CSS/Javascript shouldn't used with http/2. https://18.214.25.211/ 18.214.25.211 Warning: Https connections (Standard Port 443) found without support of the http/2 protocol via ALPN. Http/2 is the new Http-Version (old: http 1.1) with some important new features. Update your server software so http/2 is available. Only one TCP-connection per Server (that's a performance boost), Header-Compression and Server Pushs are available. Domain Sharding and Inline-CSS/Javascript shouldn't used with http/2. A Good: All checked attribute values are enclosed in quotation marks (" or '). A Info: No img element found, no alt attribute checked A Duration: 38610 milliseconds, 38.610 seconds