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SSL & Web Security Learning Center

Expert guides and tutorials on SSL/TLS certificates, encryption, PKI, and digital security. Explore the bylines, dates and sources in each guide before applying it to your environment.

199

Guides published

Oct 2, 2026

Last guide updated

Daniel Rehak

Contributor articles

Primary sources

CA/B Forum, RFCs, vendor docs

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199 articles found

Sigstore vs Code Signing Certificates: What Each One Can Actually Prove

Sigstore signs packages and images for free, and Windows ignores it completely. Why Fulcio's root never reaches the Microsoft Trusted Root Program, where a detached bundle stops mattering, and which half of your release needs a certificate you pay for.

My-SSL TeamAug 9, 202614 min

Comparisons

Code Signing vs SSL/TLS Certificates: What Actually Differs in 2026

Both are X.509 certificates from a publicly trusted CA, and neither can do the other's job. The Extended Key Usage field that blocks the substitution, the hardware key rule that only applies to one of them, and why the website certificate is now the one you renew more often.

My-SSL TeamAug 8, 202613 min

Guides

Cloudflare SSL Modes Explained: Flexible, Full, and Full (Strict)

The padlock a visitor sees only covers the hop to Cloudflare. What Off, Flexible, Full and Full (Strict) do to the second hop, why Flexible plus an origin redirect rule is a closed loop, and why Automatic SSL/TLS may have already moved your zone without asking.

My-SSL TeamAug 8, 202615 min

Security

What Is Perfect Forward Secrecy (PFS)? How TLS Protects Past Sessions

If someone steals your server's private key tomorrow, can they read the traffic they recorded today? Forward secrecy is the difference between yes and no — how ephemeral Diffie-Hellman works, why TLS 1.3 made it mandatory, and the session-ticket setting that quietly undoes it.

My-SSL Security TeamAug 8, 202613 min

Security

How to Prepare for Shorter SSL Certificate Lifetimes (47-Day Certificates)

The 47-day era is scheduled: 100-day certificates from March 2027, 47 days from March 2029, validation reuse down to 10 days. A four-step operational playbook — inventory, automation, validation, monitoring — with a year-by-year timeline.

My-SSL TeamAug 7, 202612 min

Installation

How to Install an SSL Certificate on Postfix and Dovecot

The two daemons share one certificate and want it packaged two different ways. Which objects go in which file and in what order, the Dovecot 2.4 rename that breaks configurations no certificate ever touched, and the one port where requiring encryption quietly costs you mail.

My-SSL TeamAug 7, 202616 min

Guides

How to Digitally Sign a Word Document with a Certificate

The clicking takes forty seconds; the certificate decides whether the signature means anything. Why Word checks the operating system's trusted authorities while Acrobat checks Adobe's own list, what a recoverable signature error is really telling you, and the timestamp that keeps a contract verifiable after the certificate expires.

My-SSL TeamAug 7, 202612 min

Code Signing

How to Code Sign an Electron App (Windows and macOS)

An Electron app needs two unrelated certificates, and the PFX file every older tutorial shows can no longer be issued. The three ways electron-builder reaches a hardware-held key, the session limit that decides whether a hosted CI runner can sign at all, and the macOS steps that have nothing to do with your Windows certificate.

My-SSL TeamAug 6, 202616 min

Guides

SSL Certificate for an IP Address: What You Can and Cannot Get

A public CA can certify a routable IP address at DV or OV level, never a private one and never at EV. Which addresses qualify, how control of an address is proven now that the manual methods are being retired, and why the free option lasts 160 hours.

My-SSL TeamAug 6, 202615 min

Guides

SSL Certificate for a Mail Server: Which Name, Which Type

The certificate has to match the hostname clients connect to and the host your MX record points at, never the domain after the @. Which names to request, why an S/MIME certificate cannot do this job, and what MTA-STS turns a name mismatch into.

My-SSL TeamAug 6, 202614 min

Code Signing

How to Renew a Code Signing Certificate in 2026

Renewal issues a new certificate, not an extension of the old one — new thumbprint, a 460-day ceiling since March 2026, and SmartScreen reputation that starts from zero. How to plan the overlap so the restart never reaches your users.

My-SSL TeamAug 5, 202613 min

Guides

How to Digitally Sign a PDF with a Certificate (Step by Step)

The Acrobat steps take a minute; the certificate decides whether anyone else can validate the result. Why a digital ID you make yourself always reads as unknown, which trust lists Acrobat checks on its own, and the timestamp setting that keeps a signature working after the certificate expires.

My-SSL TeamAug 4, 202614 min

All guides by topic

Every guide in the Learning Hub, grouped by subject. 199 articles covering SSL/TLS certificates, code signing, S/MIME, PKI and server configuration.

Code Signing

26 guides

SSL Basics

16 guides

Guides

61 guides

Security

55 guides

Comparisons

12 guides

Installation

25 guides

SSL Configuration

4 guides

How these guides are written and reviewed

Guides are written by Daniel Rehak and other contributors. Check each guide’s sources and date against the current issuer or platform documentation. My-SSL also sells certificates; product recommendations have a commercial relationship to this site. Send corrections with the page URL and supporting source.

Where a rule has a future effective date, the guide states what applies today and marks the future change separately. The most recently updated guide in this library was updated on Oct 2, 2026.

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