Microsoft Is Turning Off Basic Authentication: What Your Business Needs to Know
Many small businesses rely on Microsoft 365 for email and productivity tools but a big security change is happening that could affect how your devices and apps connect. Microsoft is turning off “Basic Authentication,” an older login method that’s less secure than modern alternatives. Knowing what this means and what to do can help you avoid disruptions and improve your cybersecurity.
What Is Basic Authentication?
Basic Authentication is an old way of logging in that simply sends a username and password every time a connection is made. It’s easy for attackers to intercept or reuse these credentials especially if Multi-Factor Authentication (MFA) isn’t enforced.
Microsoft has been phasing this out in favour of Modern Authentication, which uses secure tokens (like OAuth), supports MFA, and is much safer.
What’s Changing and When?
Microsoft began disabling Basic Authentication for many Exchange Online services back in 2022. Most old login methods have already been turned off, including:
- POP, IMAP, EWS, ActiveSync
- Remote PowerShell
The final piece is SMTP Auth used by devices and apps to send email. Microsoft will start rejecting Basic Authentication connections for SMTP Auth from 1 March 2026, with full enforcement by 30 April 2026.
| When | What happens |
|---|---|
| Already past | Basic Auth disabled for most legacy protocols |
| 1 March 2026 | SMTP Auth Basic Auth begins to be rejected |
| 30 April 2026 | All Basic Auth for SMTP Auth fully rejected |
Why This Matters for Your Business
If you have older applications or equipment using Basic Authentication, they could stop working when the change takes effect:
- Legacy email clients
- Printers/scanners that send mail
- Line-of-business apps using SMTP with username/password
When Basic Auth is turned off, these tools won’t be able to send emails unless updated.
What You Should Do
1. Check for Basic Auth Usage
Use Microsoft 365 admin reports or ask your IT provider to check which devices or apps still use Basic Authentication.
2. Update or Replace Older Clients
If your email software doesn’t support Modern Authentication, it’s time to upgrade or switch to one that does.
3. Reconfigure Legacy Devices
Older printers or scanners might need to be reconfigured to use a secure relay or replaced entirely.
4. Enable Multi-Factor Authentication
Enabling MFA enhances security and ensures compatibility with Modern Authentication.
Why This Is a Good Thing
Basic Authentication has long been a weak point in cybersecurity. It sends passwords with every request and doesn’t support modern protection methods like MFA. Disabling it means better protection against phishing, brute-force attacks, and data breaches.
In Summary
Microsoft’s retirement of Basic Authentication is a final push toward stronger security for Microsoft 365. While most changes have already happened, SMTP Auth will be fully switched off by April 2026.
If your business still uses older apps or devices that rely on Basic Auth, now is the time to act.
Need Help Upgrading?
JH Cloud Solutions can help assess your current setup, upgrade older systems, and ensure your business is ready for Modern Authentication. Contact us today to get started.
