Turn on the filtering gateway (MX)
Stop phishing and malware before it reaches anyone's inbox.
How it works
- Your MX record points to KnoxDefender. Every incoming message is checked (sender authentication, impersonation, payment-fraud language, links, attachments and antivirus).
- Clean mail is delivered to Microsoft 365 or Gmail within seconds. Suspicious mail is delivered with [Suspicious] in the subject, or held, depending on your policy. Malware and likely phishing are held.
Setup (about 15 minutes)
- Filtering gateway → Add domain.
- Add the TXT record shown to prove you own the domain, then click Check now.
- Confirm the delivery host (pre-filled for your provider) and save.
- Microsoft 365: create the inbound connector from KnoxDefender's IP and two mail-flow rules (skip Microsoft spam filtering for KnoxDefender's IP; reject outside mail that did not come through KnoxDefender). Google: add KnoxDefender as an inbound gateway.
- Click Turn on, then change your MX record to the value shown and click Check MX.
Important: lock down bypass
- Attackers sometimes send directly to Microsoft or Google, skipping your MX. Restrict your inbound connector to KnoxDefender's IP (step 3). KnoxDefender alerts you if it sees mail that went around the gateway.
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