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What Is an SSL Certificate and Why Do You Need One?
What an SSL certificate does, how HTTPS works and why encrypted connections are standard for modern websites.
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Guides, tips and expert explanations about SSL certificates, HTTPS security and digital trust. Learn how SSL works, compare certificate types, install certificates and troubleshoot common issues.
- Security & HTTPS
What Is HSTS and Should You Enable It?
HSTS tells browsers to load your site only over HTTPS, even when someone types or clicks an http:// link. Here is what it does, when it can break…
3 min read Read more
- Certificate Types
What Is BIMI? VMC vs CMC Certificates Explained
BIMI lets supporting inboxes show your logo next to authenticated email. A VMC or CMC certificate proves that the logo belongs to you – and the type you…
5 min read Read more
- Security & HTTPS
What Is a CAA Record and How Do You Set It Up?
A CAA record is a DNS entry that lists which certificate authorities may issue certificates for your domain. Set it up correctly and you block unauthorized issuance; set…
3 min read Read more
- Installation
Using Your Own SSL Certificate on Azure and Google Cloud
Azure and Google Cloud both offer free managed certificates, but only for some services and only at DV level. This guide shows how to bring your own Azure…
6 min read Read more
- Installation
Using a Paid SSL Certificate on AWS (ACM Import, EC2, Load Balancers, CloudFront)
AWS gives you free certificates through AWS Certificate Manager, but only for some services and only with domain validation. This guide shows when a purchased AWS SSL certificate…
6 min read Read more
- Security & HTTPS
TLS 1.2 vs TLS 1.3: Differences and How to Enable TLS 1.3
TLS 1.3 connects faster and drops the weak options TLS 1.2 still allows. Here is what differs and how to switch it on.
4 min read Read more
- Security & HTTPS
SSL vs Website Security: What an SSL Certificate Doesn’t Protect
An SSL certificate encrypts the connection to your site, but it does not stop malware, hacked plugins or data loss. Here is what else you need and how…
5 min read Read more
- Security & HTTPS
SSL Site Seals and Trust Badges: Do They Still Matter?
An SSL site seal shows visitors which certificate authority verified your domain; a TrustedSite badge shows that your site passes daily scans. Here is what each one proves…
4 min read Read more
- Certificate Types
SSL Certificates for APIs and Mobile App Backends
Every public API endpoint needs a publicly trusted SSL certificate for API traffic, or apps and partner systems will refuse to connect. This guide shows which certificate fits…
4 min read Read more
- Business & Compliance
SSL Certificate Warranty Explained: What It Covers (and What It Doesn’t)
An SSL certificate warranty protects your site visitors, not you, and only if the certificate authority made a mistake when it issued the certificate. Here is what the…
4 min read Read more
- Certificate Types
SSL Certificates for WordPress: Which One You Need and How to Install It
Most WordPress sites only need a domain-validated certificate – free from the host or paid from a CA. This guide shows which SSL certificate fits your WordPress site,…
7 min read Read more
- Certificate Types
SSL/TLS Certificates for Mail Servers (SMTP, IMAP, POP3)
Your mail server needs a publicly trusted TLS certificate that covers every hostname mail clients and other servers connect to. This guide covers ports, names, formats and the…
5 min read Read more
- Security & HTTPS
Post-Quantum Cryptography and SSL Certificates: What Changes and When
Quantum computers could one day break the math behind today's SSL/TLS. Here is what has already changed, what is still years out and what to do now.
4 min read Read more
- Certificate Types
PositiveSSL vs EssentialSSL vs InstantSSL: Which Comodo SSL to Choose
PositiveSSL and EssentialSSL are domain-validated certificates; the InstantSSL family adds organization validation. Here is how the five Comodo certificates differ and which one fits your site.
4 min read Read more
- Troubleshooting
NET::ERR_CERT_DATE_INVALID: Expired Certificate or Wrong Clock?
NET::ERR_CERT_DATE_INVALID appears when the current date falls outside a certificate's validity dates. Here is how to tell an expired certificate from a wrong clock, and how to fix…
4 min read Read more
- Installation
How to Install a Third-Party SSL Certificate on GoDaddy Hosting
You do not have to buy your certificate from GoDaddy to use it on GoDaddy hosting. This guide shows which plans accept a third-party SSL certificate, how to…
4 min read Read more
- Installation
How to Install an SSL Certificate on Nginx
Install an Nginx SSL certificate in five steps: build a full-chain file, add it to your server block, protect the key, test the config and reload. Works the…
6 min read Read more
- Installation
How to Install an SSL Certificate on IIS (Windows Server)
Install an SSL certificate on IIS in four steps: import the certificate into the Windows certificate store, add the intermediate, create an HTTPS binding and test. Covers IIS…
5 min read Read more
- Installation
How to Install an SSL Certificate on cPanel
Install an SSL certificate on cPanel in a few minutes: open SSL/TLS, paste the certificate, let cPanel fill in the key, add the CA bundle and click Install.…
5 min read Read more
- Installation
How to Install an SSL Certificate on Apache
Install an SSL certificate on Apache in five steps: copy the files, point your virtual host at them, include the full chain, test the config and reload. This…
6 min read Read more
- Installation
How to Sign a Windows Application (SignTool, Timestamping, SmartScreen)
Sign your .exe, .dll and .msi files with SignTool, add a timestamp so signatures outlive the certificate, and understand how SmartScreen reputation builds.
5 min read Read more
- Certificate Types
How to Sign and Encrypt Email with S/MIME (Outlook, Apple Mail, Gmail)
An S/MIME certificate lets you digitally sign your email and encrypt it so only the recipient can read it. Here is which level to choose and how to…
6 min read Read more
- Installation
How and When to Revoke an SSL Certificate
Revoke an SSL certificate when its private key is exposed, its details are wrong, or you no longer use the domain. Here is when revocation is required, how…
3 min read Read more
- Installation
How to Reissue an SSL Certificate (New Key, Added Domains, Lost Key)
A reissue gives you a fresh certificate inside the term you already have. Here is when you need one, what it requires and how to do it step…
4 min read Read more
- Installation
How to Move Your Website from HTTP to HTTPS (Without Losing Rankings)
Installing a certificate is only the first step of an HTTPS move. This checklist covers redirects, canonicals, sitemaps, Search Console and HSTS, in the order that protects your…
5 min read Read more
- Troubleshooting
How to Fix Mixed Content Warnings
Your certificate is installed, but the padlock is missing or parts of the page are broken. Mixed content is the usual cause, and you can find and fix…
4 min read Read more
- Certificate Types
How to Digitally Sign PDFs That Adobe Trusts
To get a valid signature in Adobe Acrobat, you sign with a certificate from a CA on the Adobe Approved Trust List. This guide shows which certificate you…
5 min read Read more
- Certificate Types
GeoTrust vs Thawte vs RapidSSL: DigiCert’s Brands Compared
GeoTrust, Thawte and RapidSSL all belong to DigiCert. They share the same infrastructure but differ in validation levels, product range and price tier.
5 min read Read more
- Troubleshooting
ERR_SSL_PROTOCOL_ERROR: What It Means and How to Fix It
ERR_SSL_PROTOCOL_ERROR means the browser and server could not agree on how to set up a secure connection. Here is how to find the cause and fix it on…
4 min read Read more
- Troubleshooting
NET::ERR_CERT_COMMON_NAME_INVALID: Causes and Fix
This Chrome error means your certificate does not list the hostname the visitor typed. Find the missing name, then cover it with the right certificate.
4 min read Read more
- Certificate Types
Digital Signature vs Electronic Signature: What’s the Difference?
An electronic signature shows that someone intended to sign. A digital signature adds certificate-based proof of who signed and that the file was not changed.
5 min read Read more
- Certificate Types
DigiCert vs Sectigo: Which Certificate Authority Should You Choose?
DigiCert and Sectigo are the two certificate authorities behind every SSL product sold at BUY-SSL. Both are trusted by every major browser; they differ in tooling, validation workflow…
5 min read Read more
- Certificate Types
Code Signing Key Storage Requirements: Hardware Tokens, HSMs and Cloud Signing
Since June 1, 2023, code signing private keys must live on certified hardware. Here is what that means for USB tokens, HSMs, cloud signing and your build servers.
5 min read Read more
- Certificate Types
Code Signing Certificate vs SSL Certificate: What’s the Difference?
An SSL certificate proves a website’s identity and encrypts the connection; a code signing certificate proves who published a piece of software and that nobody changed it. They…
4 min read Read more
- Certificate Types
Code Signing by Platform: Windows, Java, Office Macros, Drivers and macOS
One code signing certificate covers several platforms, but not all of them. Use this platform matrix before you buy.
4 min read Read more
- Troubleshooting
Cloudflare Error 526: Invalid SSL Certificate – Causes and Fix
Cloudflare error 526 appears when Cloudflare cannot validate the SSL certificate on your origin server. Here is what causes it, how to fix it and which origin certificate…
4 min read Read more
- Security & HTTPS
Certificate Transparency Explained: Logs, SCTs and Monitoring
Certificate Transparency puts every publicly trusted SSL/TLS certificate into public logs. Here is how the logs work, what an SCT proves and how to monitor certificates for your…
4 min read Read more
- Installation
How to Use ACME (Certbot, acme.sh) with a Paid SSL Certificate
Certbot and acme.sh are not only for free certificates. Connect them to a paid certificate authority with External Account Binding and let renewals run on their own.
7 min read Read more
- Certificate Types
Which SSL Certificate Do I Need?
Pick an SSL certificate by answering two questions: which hostnames it must cover, and how much identity checking you want. This guide turns common setups – subdomains, several…
8 min read Read more
- Installation
Where Are SSL Certificates Stored? Find, Export and Move Them
Certificates and private keys live in different places on every platform. This guide shows where to look, how to export them and when to reissue instead.
6 min read Read more
- Troubleshooting
Ignoring SSL Verification (curl, Python, Java): Risks and Safe Fixes
Turning off SSL verification makes an error disappear by trusting any certificate, including an attacker's. Fix the trust problem instead: point your tool at the right CA bundle…
5 min read Read more
- Business & Compliance
SSL Certificate Management: Inventory, Monitoring and Automation
To manage SSL certificates reliably, you need a complete inventory, expiry monitoring with clear owners, and automated renewal. This guide shows how to build all three and how…
11 min read Read more
- Troubleshooting
SSL Certificate Chain: Root, Intermediate and Bundles Explained
Most "not trusted" errors after an install come from a missing intermediate certificate. Here is how the chain works and how to build a correct bundle.
5 min read Read more
- Certificate Types
Self-Signed vs CA-Signed SSL: Private, Internal and Local Certificates
Self-signed certificates encrypt traffic but no browser trusts them, so they suit labs and closed systems only. For anything people visit, a CA-signed certificate or your own private…
6 min read Read more
- Security & HTTPS
Is SSL Secure? Encryption Strength, Limits and Fake Certificates
Every publicly trusted SSL certificate uses the same strong algorithms, so price does not change encryption strength. What matters is key size, hash algorithm, server configuration and how…
7 min read Read more
- Troubleshooting
SSL Certificate Expired? How to Renew It
An expired SSL certificate triggers browser warnings and breaks connections until you install a new one. Here is how to renew SSL certificates quickly, without downtime, and how…
6 min read Read more
- SSL Basics
How to Get an SSL Certificate: Step by Step
Getting an SSL certificate takes six steps: choose, buy, create a CSR, validate, install and test. Here is what happens at each step and what you need ready…
6 min read Read more
- SSL Basics
How SSL Validation Works: DCV, OV and EV Checks and Issuance Times
Every SSL certificate starts with domain control validation; OV and EV add checks on your organization. DV can be issued within minutes of DCV completing, while OV and…
5 min read Read more
- SSL Basics
How Much Does an SSL Certificate Cost?
An SSL certificate can cost nothing or a significant yearly amount, and the difference comes from four things: validation level, coverage, brand and warranty. This guide shows what…
6 min read Read more
- SSL Basics
How Long Do SSL Certificates Last? 200, 100 and 47-Day Lifetimes
As of October 2026, a public SSL certificate is valid for at most 200 days, falling to 100 days in March 2027 and 47 days in March 2029.…
5 min read Read more