SSL Certificates

Free Let's Encrypt SSL vs Paid SSL Certificates An honest comparison of free and commercial certificates, including the reasons to pay that are real and the ones that are marketing. Types of SSL Certificates: DV, OV, and EV Explained How the three validation levels really differ, what wildcard and multi-domain certificates add, and the narrow cases where paying is justified. Understanding TLS Versions and Cipher Suites Which versions to accept, the three cipher properties that matter, HSTS and OCSP stapling, and testing honestly. Understanding the Certificate Chain and Intermediates How the chain is built, the signature symptom of a missing intermediate, fixing it, and expired intermediates. What an SSL Certificate Does Not Protect A certificate is often treated as a general statement that a site is safe. It makes two narrow guarantees, and understanding their edges explains why ... What is an SSL Certificate and Why Your Website Needs One What a certificate actually protects, what it cannot vouch for, and the three steps that separate having one from actually using it. Why a Certificate Is Trusted and What a Root Store Is A certificate is trusted because something the device already trusts vouched for it. Understanding where that list lives explains several problems tha... Wildcard and Multi-Domain (SAN) Certificates The three certificate shapes, what a wildcard misses, when each fits, and checking what a certificate actually covers.

How to Generate a CSR and Manage Private Keys Generating a key and CSR properly, filling the fields, matching key to certificate, and handling keys safely. How to Install an SSL Certificate in cPanel Checking existing certificates, running AutoSSL for uncovered domains, and installing a purchased certificate without the CA bundle mistake. How to Move an SSL Certificate to a New Server Moving a certificate is copying three files and confirming they belong together. The check that takes ten seconds prevents the most common failure. How to Renew Your SSL Certificate The two renewal paths, why automatic renewal fails when it fails, and what to do when a certificate has already expired. SSL for Subdomains, Addon Domains and Mail Certificates are issued to hostnames. An account with three addon domains and half a dozen subdomains needs every one of those names covered, and the ...

How to Fix Mixed Content Warnings After Installing SSL Finding and fixing insecure resources on an HTTPS page, without corrupting serialized settings in the database. How to Force HTTPS and Redirect HTTP to HTTPS Redirecting HTTP to HTTPS without creating a loop, updating the application to match, and when HSTS is safe to add. How to Move a Site to HTTPS Without Losing Rankings Switching to HTTPS changes every URL the site has. The redirect is the part everyone does; the canonical tags, the sitemap and the internal links are ... How to Set Up HSTS Safely HSTS is a good header with an unusual property: once a browser has it, you cannot take it back. Enabling it carelessly locks visitors out of a site yo...

How to Check a Certificate from the Command Line Browser warnings are deliberately vague. One openssl command shows exactly what the server is sending, which turns most certificate problems into a fi... How to Fix Certificate Errors in Scripts and API Clients Scripts verify certificates more strictly than browsers do, and they carry their own trust list. That difference explains almost every case where curl... How to Use Client Certificates to Restrict Access Client certificates turn the usual arrangement round: the visitor proves who they are before the server responds at all. Strong, awkward, and right fo... SSL Certificate Troubleshooting Guide A lookup of the certificate warnings you will meet, what each actually means, and a diagnostic order that avoids reissuing for no reason.