How to set up a multifunction device or application to send email using Microsoft 365 or Office 365

Publisher

Microsoft

URL

https://learn.microsoft.com/en-us/exchange/mail-flow-best-practices/how-to-set-up-a-multifunction-device-or-application-to-send-email-using-microsoft-365-or-office-365

Published

2026-08-03

Updated

unknown

Accessed

2026-10-02

HTTP status

200

License

Microsoft Learn content; CC BY 4.0 for documentation text per MicrosoftDocs repo, verify before reuse; no-redistribution; short excerpts and locators only

Source notes citing this source

• Microsoft states that client SMTP submission with Basic authentication in Exchange Online is scheduled for deprecation. Its listed alternatives are High Volume Email (internal recipients), Azure Communication Services Email, or relaying through an on-premises mail server. in context
• Microsoft 365 Direct Send (unauthenticated, MX endpoint, port 25) delivers only to the tenant's own recipients; mail to external recipients is rejected. Microsoft says it is working on an option to disable Direct Send by default. in context
• Microsoft 365 SMTP relay uses the tenant MX endpoint on port 25 and authenticates through an inbound connector, using a TLS certificate whose Subject/SAN matches an accepted domain or a static, unshared public IP. It needs no licensed mailbox and can relay to external recipients. in context
• For client SMTP submission to Exchange Online, Microsoft specifies smart host smtp.office365.com (not an IP address), TCP 587 (recommended) or 25, STARTTLS with TLS 1.2 or 1.3, and the credentials of a licensed mailbox. in context
• SMTP AUTH is disabled by default for Microsoft 365 organizations created after January 2020 and must be enabled per mailbox for client SMTP submission. Basic-auth SMTP submission is incompatible with Microsoft Entra ID security defaults. in context

Cite this source record

APA

WarmTransfer. (2026, August 3). How to set up a multifunction device or application to send email using Microsoft 365 or Office 365. WarmTransfer. https://warmtransfer.net/knowledge/sources/ms-learn-mfd-app-send-email-m365

BibTeX

@misc{warmtransfer-ms-learn-mfd-app-send-email-m365,
  title  = {How to set up a multifunction device or application to send email using Microsoft 365 or Office 365},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/sources/ms-learn-mfd-app-send-email-m365},
  note   = {Microsoft, accessed 2026-10-02}
}