Microsoft 365 SMTP after Basic auth ends: printers, apps and NAS

From the end of December 2026 Microsoft 365 turns off password (Basic) sign-in for SMTP AUTH by default. Scanners, printers, WordPress sites, NAS boxes and scripts that send through smtp.office365.com with a username and password will fail with 535 5.7.139. Pick your device for the exact fix.

• HP printers and MFPs – HP Enterprise and Managed MFPs on current FutureSmart 5 firmware can sign in to Microsoft 365 with OAuth 2.0 in the Scan to Email wizard. HP…
• Canon imageRUNNER ADVANCE and i-SENSYS/imageCLASS – imageRUNNER ADVANCE DX and newer imageCLASS/i-SENSYS models can send with Microsoft OAuth 2.0: Remote UI → Settings/Registration → Send (or …
• Ricoh MFPs and printers – Ricoh has released OAuth 2.0 firmware for Exchange Online (from July 2025) for the IM, MP, SP and P models on its support list. Update, then…
• Xerox AltaLink and VersaLink – Xerox has OAuth 2.0 firmware (Device Code Flow) for current AltaLink and VersaLink models. In the Embedded Web Server open Apps → Email → SM…
• Brother printers, MFCs and scanners – Many Brother MFC, DCP, HL and ADS models support OAuth 2.0 for Exchange Online, some only after a firmware update: check Brother's support l…
• Konica Minolta bizhub – Most bizhub i-Series and many older bizhub models get Microsoft 365 OAuth 2.0 from firmware F233-G00-T8(00) or F000-GC3-YE(00). After the up…
• Kyocera TASKalfa and ECOSYS – Newer Kyocera TASKalfa MZ and ECOSYS MA/PA models sign in to Microsoft 365 with OAuth2 in Command Center RX, and TASKalfa xx54ci and x004i m…
• Sharp MX and BP series – Sharp documents OAuth 2.0 for Microsoft 365 on its BP-series MFPs: choose OAuth 2.0 in the SMTP settings and get the token at the control pa…
• Lexmark – Lexmark printers support Microsoft 365 OAuth 2.0 from firmware FW24 (240.043 or later). Update, register the printer in the Embedded Web Ser…
• Epson WorkForce and EcoTank business – Epson added OAuth2 for Microsoft Exchange Online to listed WorkForce, WorkForce Pro, WorkForce Enterprise and EcoTank models by firmware upd…
• WordPress SMTP plugins (WP Mail SMTP, FluentSMTP, Post SMTP) with Microsoft 365 – Move the plugin off Other SMTP (smtp.office365.com plus a password) to its Microsoft mailer: WP Mail SMTP 365 / Outlook (Pro), FluentSMTP Ou…
• Synology DSM and QNAP QTS / QuTS hero email notifications with Microsoft 365 – Synology DSM and QNAP Notification Center both have an Outlook sign-in option (OAuth) for alert email. Use it instead of a custom SMTP serve…
• PowerShell Send-MailMessage with Microsoft 365 – Send-MailMessage is obsolete (Microsoft Learn) and logs in to smtp.office365.com with a password, which fails once Basic auth is off. Replac…
• Microsoft 365 SMTP relay connector (any printer, scanner, NAS or app) – Create an inbound connector in the Exchange admin center (Mail flow → Connectors, from Your organization's email server to Office 365) that …

Background and dates: Microsoft 365 SMTP AUTH Basic auth retirement.

Check your domain's SPF before you switch to a relay