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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.

205

Guides published

Oct 22, 2026

Last guide updated

Daniel Rehak

Contributor articles

Primary sources

CA/B Forum, RFCs, vendor docs

Browse by Topic

205 articles found

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 with a new thumbprint, capped at 460 days since March 2026. What the CA may reuse from your last validation (825 days Standard, 398 EV), why EV should renew before expiry, and what Microsoft says about SmartScreen.

My-SSL TeamAug 5, 202611 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

SSL Basics

X.509 Certificates Explained: Fields, Extensions, and Structure

The object behind every SSL/TLS, code signing and S/MIME certificate, opened up field by field. What the tbsCertificate holds, which v3 extensions do the real work, why browsers ignore the Common Name entirely — and the four things a public CA must add in 2026 that RFC 5280 never asked for.

My-SSL TeamAug 3, 202615 min

Code Signing

How to Verify a Code Signature (Windows, Linux & Java)

One verdict, three separate checks — integrity, trust chain, and time. The exact commands for SignTool, PowerShell, osslsigncode and jarsigner, what each status value means, why /pa decides the answer on Windows, and how to gate a build on the exit code instead of the log text.

My-SSL TeamAug 2, 202615 min

Security

What Is Certificate Transparency? CT Logs and SCTs Explained

Every publicly trusted certificate is published in append-only logs before it works in a browser. How CT logs, SCTs and precertificates fit together, why Chrome wants two SCTs on short certificates and three on long ones, what Firefox 135 changed, and the hostname leak nobody warns you about.

My-SSL TeamAug 1, 202614 min

Code Signing

How Long Does Code Signing Validation Take?

Certum lists 1–5 days for a Standard code signing certificate and 1–7 days for EV. The steps before that clock starts, what Certum checks, the documents that make an order wait, and why a cloud certificate needs no shipping after issuance.

My-SSL TeamAug 1, 20268 min

Guides

How to Sign a ClickOnce Application (Step by Step)

Signing a ClickOnce app means signing its two manifests with mage, not the EXE. The three-command order, how to reach a key on a hardware token, timestamping, and the certificate-renewal trap that forces every user to reinstall — now that 460-day certificates make renewals annual.

My-SSL TeamJul 31, 202612 min

Security

Shor's Algorithm Explained: How It Breaks RSA and ECC

Shor's algorithm factors large integers and solves discrete logarithms in polynomial time, which breaks RSA, Diffie-Hellman, and ECC/ECDSA. How it actually works, why AES and SHA-2 survive, how many qubits it would really need, and what it means for the certificates you run today.

Daniel RehakJul 31, 202614 min

All guides by topic

Every guide in the Learning Hub, grouped by subject. 205 articles covering SSL/TLS certificates, code signing, S/MIME, PKI and server configuration.

Code Signing

28 guides

SSL Basics

16 guides

Guides

63 guides

Security

56 guides

Comparisons

13 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 22, 2026.

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