What it is
MxGuard is a cloud-delivered email security gateway. Point your MX record at it and every inbound message is scored, sorted, and forwarded on to your real mail server — with a single web console to manage everything.
Your MX record points at us. Inbound mail flows through a hardened SMTP pipeline before it ever touches your backend. No firewall changes, no agents to install.
A machine-learning classifier decides the easy 95% in milliseconds. Borderline messages are handed to Claude (Anthropic's LLM), which reads them the way a person would before a verdict is reached.
A web app for every customer — live feed, quarantine, allow/block rules, score breakdowns, daily digest, audit log, domain management. No support tickets needed.
Want the technical pipeline detail? See how it works →
The problem
Rule-based and Bayesian filters were designed for an era of obvious spam. They struggle with the messages that matter most — the ones written carefully, sent from clean infrastructure, addressed to a specific person, asking for one thing.
CEO impersonation, invoice redirection, gift-card fraud. Clean SPF/DKIM. No malicious payload. Rule filters see nothing wrong.
accountss-secure.io, compaany-co.net. Bayesian filters treat them as just another word.
Grammar, tone, formatting indistinguishable from real correspondence. Pre-2023 heuristics were never trained for this.
Legitimate bulk mail, mailing lists, transactional notifications — flagged because they match a rule from 2014.
What's included
MxGuard runs in our UK-based cloud. Customers point their MX records at our infrastructure and start receiving filtered mail within minutes. There's nothing to deploy on your premises, no agents to install, no firewall rules to add.
Subscription pricing means no up-front capital investment and no surprise upgrade costs. Scale up or down month-to-month as your business changes.
Full feature list on the features page.
Threat coverage
Six classes of threat, covered by the layered pipeline and the hybrid AI brain working together.
Credential-harvest pages, fake login flows, OAuth-consent traps. URL reputation plus Claude's analysis of the message asking for the click.
CEO fraud, invoice redirection, gift-card scams, supplier impersonation. Payload-free attacks — where the LLM layer is strongest.
ClamAV scans every attachment, including archives. Macro-bearing Office docs and HTML smuggling are scored heavily.
Classic spam, snowshoe campaigns, hailstorm runs. DNSBLs catch the easy 80%; the ML model handles the rest with near-zero false positives on legitimate bulk.
Homoglyph attacks, doubled letters, ccTLD swaps. Detected at envelope, From header, and reply-to. Cross-checked against your sender history.
SPF / DKIM / DMARC enforcement plus ARC sealing through forwarding. Fake bounces and forged From addresses are rejected at SMTP time.
Who it's for
Enterprise-grade detection at SMB pricing. Self-service onboarding, no procurement process. Most customers are live within a working day.
Multi-domain customer accounts, per-customer dashboards, ARC sealing for forwarding, Prometheus metrics. Designed to be wholesale-friendly.
Manage email security for multiple clients from one console. Per-client billing, audit logs, and a forum for tracking what's shipping next.
eFa reaches end-of-life this July. MxGuard is a direct replacement — same MX-fronting role, modern detection, dedicated migration path. See the migration plan ↓
Positioning
For decades, mail security has meant stacking together open-source rule engines and Bayesian filters — or paying enterprise-suite prices. MxGuard replaces both.
Hand-tuned rule trees that are slow to adapt to modern spam, produce frequent false positives on legitimate bulk mail, and require expert administration to maintain.
eFa end-of-life: July 2026
Powerful, but priced in the thousands per year per organisation, bundled with features you won't use, and locked into multi-year contracts. MxGuard delivers the same hybrid-AI architecture at a fraction of the cost, with month-to-month billing.
For a feature-by-feature comparison see the features page.
Migration
MxGuard runs in front of the same backend mail server you already have. The only thing that changes is which IP your MX record points at.
eFa end-of-life: July 2026
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