Microsoft Exchange

Connecting MXGuard to Exchange Server 2016/2019 and Exchange Online.

Exchange Server (on-premises)

After changing your MX records to MXGuard's servers, configure Exchange to accept mail only from our IP addresses:

Create a Receive Connector

In the Exchange Admin Center → Mail flow → Receive connectors → New. Type: Internet. Name: "MXGuard".

Restrict to allowed IP addresses

In the "Remote IP ranges" field, remove the 0.0.0.0–255.255.255.255 range and add only our subnets:

88.198.102.232/29

62.76.100.176/29

62.76.113.32/27

Set the target server in MXGuard

In the MXGuard panel → Domains → set your Exchange server's FQDN as the delivery target server.

Exchange Online (Microsoft 365)

For Exchange Online, the target server looks like company-com.mail.protection.outlook.com — you can find it in your domain's MX records before switching to MXGuard.

We also recommend configuring Enhanced Filtering for Connectors in the Security & Compliance Center, so Microsoft doesn't re-score mail that already passed our filter.

If you use Exchange Online, be sure to add an SPF record that includes include:spf.mxguard.net, so Microsoft accepts mail from our IPs.