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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

    Code Signing
    28 articles
    SSL Basics
    16 articles
    Guides & Tutorials
    63 articles
    Security
    56 articles
    Comparisons
    13 articles
    Installation
    25 articles
    SSL Configuration
    4 articles

    205 articles found

    Security

    Does the Cyber Resilience Act Require Code Signing?

    Regulation (EU) 2024/2847 never mentions code signing, and every vendor selling you a certificate for it is describing one control out of a set. What Annex I actually asks for, why the September 2026 deadline has nothing to do with signing while the December 2027 one does, and the question the regulation never asks that decides whether you need a publicly trusted certificate or your own key. Plus the arithmetic nobody does: a five-year support period against a 460-day certificate.

    My-SSL TeamAug 25, 202615 min
    Security

    ACME Challenge Types: Which One Your Setup Can Actually Use

    Three challenges are in general use and a fourth is arriving, and the one you can pick is decided by your infrastructure rather than your preference. What http-01, dns-01, tls-alpn-01 and dns-persist-01 each demand, the redirect rules that make most HTTP-01 exception rules unnecessary, why multi-perspective validation broke setups that had worked for years, and why the domain-validation reuse window falling from 398 days to 10 by 2029 turns the challenge choice into an architectural one.

    My-SSL TeamAug 24, 202614 min
    Security

    SSL Certificate Monitoring: What to Watch, and From Where

    Monitoring a certificate means watching four different things, and most setups watch one. What your CA account, a Certificate Transparency log, the file on the host and a probe of the live endpoint each see — and what each one is blind to. Why the 200-day maximum in force since March 2026 moved the everyday failure from "nobody renewed it" to "it renewed and never reached the server", and why a fixed 30-day expiry warning stops meaning anything by 2029.

    My-SSL TeamAug 24, 202613 min
    Guides

    S/MIME Certificate Renewal: What Expiry Does to Old Mail

    An S/MIME certificate expires; the private key it names does not stop working. Why every message encrypted before the end date still decrypts as long as the key survives the renewal, why old signatures are judged by the recipient's mail client rather than by you, what the 825-day ceiling and the 30-day mailbox check mean in practice, and the export step that has to happen before anything else.

    My-SSL TeamAug 23, 202613 min
    Security

    Certificate Pinning: What to Pin, and When Not To

    A pin is a choice of height in the certificate chain, and that choice decides how often renewal becomes an outage. Why leaf pinning dies at every reissue while an SPKI pin survives if you reuse the key, what the shrinking lifetime schedule does to the arithmetic between now and 2029, how Android and Apple actually implement pinning, the backup-pin rotation order that does not break clients, and the two branches of the decision tree that end in "do not pin".

    My-SSL TeamAug 22, 202614 min
    Guides

    Code Signing Certificates for macOS: What Actually Works

    No publicly trusted code signing certificate gets a Mac app past Gatekeeper. macOS accepts one signing hierarchy for distributed software and Apple is the only issuer inside it. What the Developer ID and notarization route actually requires, the four gates Gatekeeper runs before a first launch, what your CA certificate still signs (including Windows binaries built on a Mac), and the key-storage and validity asymmetries that catch cross-platform teams shipping to both platforms.

    My-SSL TeamAug 22, 202613 min
    Guides

    Using One SSL Certificate on Multiple Servers: Licences, Keys and Reissues

    One certificate can secure any number of servers, because nothing in TLS counts installations, but three separate questions get asked as one here. Which names the certificate covers is set by the request, how many servers may run it is a commercial licence term, and how many copies of the private key exist is decided every time you install. Why the copy-the-key habit stopped scaling when lifetimes fell to 200 days in March 2026, and when a free reissue per host is the better default.

    My-SSL TeamAug 22, 202613 min
    Guides

    SSL Certificates for Internal Server Names: The Four Options Left

    No publicly trusted CA has been allowed to certify a name like server01, anything ending in .local, or anything under the .internal domain since 1 November 2015, and the certificates that named one were revoked by October 2016. The four routes that remain, how split-horizon DNS and the ACME dns-01 challenge put a publicly trusted certificate on a host that answers nothing from outside, the pre-flight lookup that breaks most first attempts, and what certificate transparency publishes about your estate either way.

    My-SSL TeamAug 21, 202614 min
    Guides

    Signed EXE Flagged as a Virus: Why It Happens and How to Fix It

    A code signing certificate answers one of the three checks a Windows download passes, and the malware verdict is not it. Microsoft's own developer guidance says a signature will not bypass a behavioural classifier. How to tell which of the three gates actually stopped your build, why reputation is pooled across everything one certificate signs, the prevalence rule that blocks brand-new releases on managed fleets with no detection involved, and how to file a false positive that gets read.

    My-SSL TeamAug 21, 202613 min
    Guides

    SafeNet Authentication Client: Setup, PINs, and Fixing Token Errors

    The middleware that turns a plugged-in USB token into something SignTool, jarsigner, and browsers can actually use, and where most code signing setups now break. Which SafeNet 5110 model your CA shipped, why installing SAC and SafeNet Minidriver together produces the intermittent failures nobody can reproduce, the four checks that isolate a token-not-detected error, and why the Administrator PIN is the one secret nobody outside your team can help you recover.

    My-SSL TeamAug 20, 202612 min
    Security

    Code Signing Certificate Revoked: What Breaks and What to Do Next

    Revocation is the one certificate operation nobody can undo, and it lands unevenly: one date recorded by the CA splits your release history into signatures that keep validating and signatures that stop. Which side each build falls on, why the reason you give changes the blast radius, what a customer actually sees when a revoked chain is rejected, and the order to recover in. Containment first, replacement certificate last, because that is the step that takes days.

    My-SSL TeamAug 20, 202613 min
    Installation

    How to Install an SSL Certificate on vCenter Server (vSphere 8)

    Every guide to this opens with the certificate-manager menu. The question that decides the outcome comes earlier: a publicly trusted CA cannot issue for vcenter.corp.local, and a great many appliances are named exactly that. Which of the four vSphere certificate stores actually needs replacing, why the wildcard you already own is unusable, what the SubjectAltName and PNID have to agree on, and why a 200-day certificate on an appliance with no ACME client is a decision about maintenance windows rather than about one certificate.

    My-SSL TeamAug 19, 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

    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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