Microsoft 365 SMTP AUTH: keep scan-to-email working (free draft preview)

Printers, scanners and old apps that send mail through Microsoft 365 with a username and password may stop sending when Basic authentication for SMTP AUTH is turned off by default. This is a free preview of a small kit that helps an admin find those senders and pick a fix path.

Read this first.

Independent and unofficial. Not Microsoft software; not affiliated with, endorsed or sponsored by Microsoft. "Microsoft" and "Microsoft 365" belong to Microsoft.
Draft v0.1, 18 Oct 2026. Not tested on a real tenant or device.
Parser header row unverified. Microsoft documents the report's column labels but publishes no sample CSV, so the literal header row of the exported file is not verified. The analyzer matches loosely and says when it had to guess.
PowerShell script untested. No PowerShell command in the kit has been run against a tenant.
Not legal, security or tenant-specific advice. Check every step against Microsoft Learn before changing production mail flow.

What Microsoft says (as fetched 18 Oct 2026)

From Microsoft's Jan 27 2026 post "Updated Exchange Online SMTP AUTH Basic Authentication Deprecation Timeline":

Now to December 2026: behavior remains unchanged.
End of December 2026: Basic authentication will be disabled by default for existing tenants; administrators will still be able to enable it if needed.
New tenants created after December 2026: unavailable by default; OAuth is the supported method.
Second half of 2027: Microsoft will announce the final removal date.

Dates can change. Read the live post: techcommunity.microsoft.com/blog/exchange/updated-exchange-online-smtp-auth-basic-authentication-deprecation-timeline/4489835

What is in this preview

Basic-auth finder (analyzer)
Paste or open the "SMTP AUTH clients" report. It lists senders still on Basic auth and suggests fix paths. It runs entirely in your browser: no network requests (blocked by its security policy), nothing stored, no cookies.

Runbook (PDF) · HTML
Inventory, four questions per sender, fix paths with sources, test plan, rollback, and a careful stopgap section.

Device and app guides
Generic device · HP FutureSmart · Brother · Canon · Ricoh · Xerox · Konica Minolta · WordPress · Line-of-business app
Vendor statements are the vendors' own claims, not tested by us.

Evidence register
Quotes and links for every sourced claim, and what was not verified.

Honest limits

Evidence labels: [V] page opened and text is on it; [A] vendor claim; [P] third-party write-up; [G] guess; [I] inference.
Re-enabling Basic authentication lowers security. The runbook treats it as a short, owned exception, not a fix.
No security guarantee. No device or tenant was tested. No third-party relay vendors were evaluated.

This preview is free, collects no information, has no sign-up and no forms, and makes no network requests.