Download

SMTP-365 appliance 0.4.1

Every download is the full product with a 30-day evaluation built in. Deploy it, open the address shown on the console, and the setup wizard takes you through everything in about 20 minutes. Enter a licence key whenever you're ready; nothing is reinstalled.

VMware · VirtualBox

OVA virtual appliance

Import into ESXi, Workstation, Fusion or VirtualBox. 1 vCPU, 2 GB RAM, 16 GB thin disk preset.

Download OVA · 728 MB

Hyper-V

VHDX disk image

Create a Generation 2 VM with 2 GB RAM and attach this disk. Set Secure Boot to Microsoft UEFI Certificate Authority or turn it off.

Download VHDX · 1.9 GB

Proxmox · KVM

qcow2 disk image

Import as a VirtIO disk; UEFI or BIOS boot both work.

Download qcow2 · 746 MB

Any hypervisor · bare metal

Installer ISO

Boots and installs unattended, then reboots into the appliance. Erases the first disk of the machine it boots on. Needs internet access during install.

Download ISO · 1.0 GB

After it boots

The console shows the admin address, for example https://192.168.1.57/. Accept the self-signed certificate warning for now.
Sign in as admin with the password you gave at deployment or, if you gave none, the one-time password the appliance shows on its console screen. The wizard asks you to replace a one-time password first.
Work through network, ports, licence (or continue the trial), Microsoft 365 sign-in, and the sender mailbox.
Add SharePoint routes, point your printers at the appliance's address on port 2525, and send a test scan.

The installation guide covers each step, including how to restrict sending to a single mailbox.

Already running SMTP-365?

Use Software update → Check for updates on the appliance, or upload the signed bundle by hand. An appliance on 0.3.8 updates straight to 0.4.0; installing it needs a licence whose maintenance runs to 4 October 2026 or later.

Update bundle 0.4.1 · 42 MB

Verify your download

SHA-256 checksums. On Windows: Get-FileHash file -Algorithm SHA256. On Linux/macOS: sha256sum file. Or download SHA256SUMS. Each file also has a .sha256 beside it on the download server.

Signed checksums. SHA256SUMS is signed with the SMTP-365 release key: download SHA256SUMS.sig and the public key, then check with OpenSSL 3: openssl pkeyutl -verify -pubin -inkey smtp365-release-key.pem -rawin -in SHA256SUMS -sigfile SHA256SUMS.sig followed by sha256sum -c SHA256SUMS --ignore-missing.

File	Size	SHA-256
smtp365-0.4.1-amd64.ova	727,705,600	cf0c9a697f3dc1c56d442def6b9a3e19757537a8046c608c993b2f64d01f2ae7
smtp365-0.4.1-amd64.vhdx	1,853,882,368	7111af3af17068970a4fb5a2893d271b7ec88cd8bac41bfe98360729d86e05c2
smtp365-0.4.1-amd64.qcow2	745,930,752	12e37cbd662ee92bb271c0ff5c3c46f4e0d28f48a7463cfcce7aa417cd768f1d
smtp365-0.4.1-amd64.iso	1,029,701,632	73e951ad3c4b2ba00f3c615e3ae68cbbaa81f398598ded9197c998baffb63bf6
smtp365-0.4.1.smtp365-update	41,566,943	242ec6690eca7017751bb84eee6b5f678114e43aa06715708d72bc3d4f57564e

Requirements

1 vCPU, 2 GB RAM, 16 GB disk (a larger virtual disk is used in full at first boot).
A LAN address the printers can reach, by DHCP or static.
Outbound HTTPS to login.microsoftonline.com, graph.microsoft.com and licence.smtp-365.com. These are the only connections the product makes by itself. Operating-system updates (from 0.3.8) are installed only when your administrator asks for them on the Software update page, which needs outbound HTTP to deb.debian.org and security.debian.org. Debian's own automatic updates are not installed; if you add them, SMTP-365 does not manage them.
A Microsoft 365 Global Administrator for the one-time sign-in during setup.

Linux package, Raspberry Pi and Windows Server editions are on the roadmap. By downloading you accept the licence terms.