send25

Setup guide

Pointing your equipment at send25.

Every device asks for the same handful of things, just under different names. Here's what to enter, and what each brand calls it.

The settings By brand Microsoft 365 Apps & servers Testing it If it doesn't work

The settings

We'll tell you which of these two applies to you when your account is set up. Most offices with a fixed internet connection use the first; everyone else uses the second.

Don't guess. If you're not sure which you have, use the username and password — it works on any connection, including one whose IP address changes.
SMTP settings READY
Server
mail.send25.net
Port
25or 587 — both work
Encryption
Off, or STARTTLSwhatever the device supports
Username
— none —
Password
— none —
From address
you@yourdomain.camust be your own domain

What your brand calls these fields

Menu wording varies between models and firmware versions, so treat the paths below as a strong hint rather than gospel. The settings themselves are identical everywhere.

CANON

imageRUNNER / imageCLASS

Remote UI → Settings/Registration → Send → Network Settings – E-mail/I-Fax Settings. Set SMTP Server and E-mail Address. If you're using a password, turn on SMTP Authentication (SMTP AUTH). Canon often hides the port under Communication Settings — check it's 25 or 587, not 465.

RICOH

Aficio / MP / IM series

Web Image Monitor → Device Management → Configuration → Email. Fill SMTP Server Name, Port No. and Administrator Email Address. Set Use Secure Connection (SSL) to Off unless you're on 587 with STARTTLS.

XEROX

WorkCentre / VersaLink / AltaLink

CentreWare / Embedded Web Server → Properties → Connectivity → Setup → SMTP. Xerox insists on a valid From address — put a real address on your own domain there, not noreply@localhost. That single field causes most Xerox failures.

SHARP

MX series

Web page → System Settings → Network Settings → Services Settings → SMTP. Set Primary Server, Port Number and Sender Address. Sharp's Connection Test button is genuinely reliable — use it.

KONICA MINOLTA

bizhub

Web Connection → Network → E-mail Setting → E-mail TX (SMTP). Enter SMTP Server Address and Port Number. Leave SSL/TLS as None for port 25. The device's own email address goes under Administrator settings and must be on your domain.

HP

LaserJet / OfficeJet / PageWide

Embedded Web Server → Scan/Digital Send → E-mail Setup, or the Scan to Email Wizard. Choose the manual option rather than letting the wizard pick a provider. HP defaults to port 25 with no encryption, which suits us fine.

BROTHER

MFC series

Web Based Management → Network → Protocol → SMTP (Advanced Settings). Set Server Address, Port, and Device E-mail Address. Set Server Authentication Method to None for IP-based, or SMTP-AUTH if we gave you a password.

LEXMARK / KYOCERA

and everything else

Look for E-mail Setup, SMTP Setup or Send Settings in the device's web interface. If a field exists for it, our settings fit. Stuck? Send us the make and model and we'll find it with you.

Microsoft 365 and Google Workspace

If your devices currently relay through Microsoft or Google and that stopped working, you have two options. Pointing the devices straight at us is almost always simpler.

  1. Point the devices at us instead — recommended

    Change the SMTP server on each device to mail.send25.net using the settings above. Nothing changes in your Microsoft 365 or Google tenant at all, and you stop depending on a connector that can be switched off again.

  2. Keep the devices pointing at your mail server

    If your equipment must keep talking to an internal server, that server can forward to us instead — see relaying from another mail server in the docs. You'd still authenticate to us the same way.

Worth knowing: mail you send through us still comes from your domain. Recipients see your company, not ours, and replies come back to you as normal.

Applications and servers

Anything that speaks SMTP works. A few common shapes:

Line-of-business appPoint its mail settings at mail.send25.net, port 587, with the credential we issue. Set the From address to a real mailbox on your domain so replies reach someone.
Accounting / ERPSame. If it only supports port 25 without encryption, that's fine — use the IP-based setup.
Alarm / building systemsThese often support only plain SMTP on 25 with no authentication. That's exactly the case we exist for.
Websites and formsUse port 587 with a credential. Give each site its own credential so one can be revoked without touching the others.
A server you runSee relaying from another mail server — there's a worked Postfix example.

Testing it worked

  1. Use the device's own test button

    Most copiers have Test or Connection Test next to the SMTP settings. A pass means it reached us and we accepted the connection.

  2. Scan something to your own address

    The real test. If it arrives, you're done. If it doesn't, check the junk folder before anything else — that usually means DNS records are still outstanding.

  3. Check your console

    Sign in and open Messages. Every attempt shows up there with its outcome — sent, deferred or bounced — and the reason. You'll usually see the answer before you finish reading this sentence.

If it doesn't work

The device says it can't connect at all

Something between the device and us is blocking the connection — usually the office firewall or the internet provider blocking outbound port 25. Try port 587 instead; it's blocked far less often. If neither connects, your provider is filtering outbound mail and we'll help you work around it.

"Authentication failed" or 535

The username or password is wrong, or the device is set to the wrong authentication type. The username is the full string we gave you including the @mail.send25.net part — some devices silently cut it at the @ sign. Check authentication is set to SMTP-AUTH / LOGIN, not POP before SMTP.

"Access denied" or the connection is rejected

Your office IP isn't on our allow-list — and the most common reason is that it changed. Most business internet connections don't have a truly fixed address. Tell us the new one, or switch to a username and password so it stops mattering.

"Not authorised to send as this domain"

The device's From address is on a domain that isn't registered to your account. Often it's a leftover default like copier@localdomain. Set it to a real address on your own domain.

Mail sends but arrives in junk

Your DNS records aren't finished. Sign in and open the domain's DNS setup page — it checks live DNS and tells you exactly what's missing. All three green means the authentication side is correct.

It worked, then stopped weeks later

Two usual suspects: your office IP changed (see above), or someone replaced the copier. Both show up immediately in Messages in the console.

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