Xeams

Xeams is an email server and email firewall from Synametrics Technologies. Small and mid-sized organisations use it to filter spam and viruses in front of Exchange, Microsoft 365 or another mail server, or to run complete SMTP, POP3 and IMAP mail hosting on their own hardware. A Xeams download gives you one Java-based product that covers both roles, and it runs on Windows, Linux, macOS and other UNIX systems.

Licensing needs a clear explanation, because older reviews call Xeams free. Since 2017 it has two editions. The Enterprise Edition is paid and licensed yearly by number of users. The Community Edition costs nothing but is restricted: it is licensed for personal and hobbyist use, and spam filtering in it works for up to five users. That makes Xeams shareware (conditionally free) for any business use. A new installation runs with Enterprise features for an evaluation period first.

Xeams at a glance

What it does

• Works as an email firewall (smart host) in front of another server, or as a full mail server with built-in SMTP, POP3 and IMAP.
• Filters spam with adaptive rules plus SPF, DKIM and DMARC checks; recent versions add AI-powered filtering in the paid edition.
• Blocks viruses and embedded macros in Word and Excel attachments, and lets admins look inside attachments without opening them.
• Archives every inbound and outbound message automatically, with fast search for compliance requests.
• Encrypts sensitive mail end to end (Enterprise Edition) and helps users send large attachments.
• Sits in front of Microsoft 365 to add extra filtering, reporting and archiving.
• Includes live monitoring and usage reports. The yearly report even estimates the time saved by blocking junk.
• Includes a web admin console and, since version 10.3, the Xeams Web Access (XWA) webmail client, a redesigned interface and dark mode.

How sysadmins use it

Filter spam for an existing mail server on the same machine

1. Move your existing server’s SMTP listener off port 25, for example to 2500. If you also plan to use Xeams IMAP and POP3, move those ports too.
2. Install Xeams and open http://localhost:5272; the setup wizard starts on the first login.
3. In the wizard, pick the email-firewall (regular SMTP server) role and enter localhost:2500 as the corporate mail server that filtered mail is delivered to.
4. Send test messages and confirm that clean mail arrives and junk lands in the Xeams quarantine.

Put Xeams in front of Microsoft 365 or a remote server

1. Install Xeams on its own Linux or Windows host with a public IP and a reverse DNS record.
2. Set the downstream server (for example your Exchange Online inbound host) as the delivery target in the wizard.
3. Point your domain’s MX record at the Xeams host, and allow inbound SMTP on the downstream side only from the Xeams IP.
4. Watch Live Monitoring for a few days and tune the filter rules before you tighten them.

Check firewall rules before go-live

1. Open 25/TCP in and out for SMTP.
2. Allow outbound 53 (DNS), 43 (WHOIS, used by the junk filter) and 80/443 (rule and program updates).
3. Open 143/993 (IMAP) and 110/995 (POP3) only if users fetch mail from Xeams.
4. Keep 5272 (admin console) and 7865 (embedded database) closed to the internet.

Install and first run

• Windows: run the installer as administrator. The vendor advises against installing into “Program Files”. Xeams installs and starts a Windows service; manage it from the Services console. Then browse to http://localhost:5272.
• Linux: the recommended method is the one-line terminal installer from the official Linux page, run with sudo. It asks for an install folder (default /opt), creates start-up scripts and starts the service. Some platform packages do not bundle a Java runtime; in that case install a JRE first and make sure java is in the PATH.
• macOS, Solaris, other UNIX, Synology: separate packages are offered on the official site.
• First login: the admin console runs on port 5272. Register the copy when the console asks; registration is free and assigns your installation its serial number.
• Gotchas: only one process can own port 25, so another SMTP service on the box must move first. Many residential and cloud providers block outbound port 25, and Xeams cannot work around that.

Limitations

• The Community Edition is for personal and hobbyist use only, and its spam filtering stops at five users; business use requires the paid edition.
• Clustering, OAuth 2.0, SIEM integration, end-to-end encryption and the REST API are Enterprise-only.
• The admin console is functional but dense, and many settings have no wizard.
• Running your own internet-facing mail server means owning IP reputation, PTR records and blocklist monitoring. Xeams does not remove that work.
• It is Java-based, so memory use is higher than lightweight MTAs such as Postfix.

Xeams vs alternatives

FAQ

Is Xeams free?

Not for business use. The Community Edition is free for personal and hobbyist use, with spam filtering for up to five users. Commercial use needs the paid Enterprise Edition, so we list Xeams as shareware (conditionally free).

Where can I find the Xeams changelog and manual updates?

The official changelog is on xeams.com. Xeams also fetches rule and program updates itself over outbound HTTP/HTTPS, so do not block 80/443 outbound.

How do I install Xeams on Linux?

Use the one-line terminal installer from the official Linux download page, run it with sudo and accept the default /opt folder. Then open port 5272 in a browser to finish the setup wizard.

Is there a Xeams version for Windows?

Yes. The Windows installer sets Xeams up as a service. Install it outside “Program Files”, as the vendor recommends.

Does Xeams run on QNAP or Synology?

The vendor publishes a Synology package. For QNAP, the generic Linux build is the usual route, provided a Java runtime is available.

What port is the Xeams admin console on?

The admin console is on 5272/TCP. Keep it on the LAN or behind a VPN rather than publishing it to the internet.

What is a good Xeams alternative?

For filtering only, Proxmox Mail Gateway is free and open source. For a Windows mail server, consider hMailServer or MailEnable.

Last checked against official sources: 1 October 2026 (developer website: xeams.com). Versions and licence terms change — confirm on the developer's site before deploying in production.