Starting August 1, 2026, Microsoft will begin rolling out this security update worldwide, with completion expected by December 31, 2026.
Once the change reaches your tenant:
❌ POP and IMAP connections using TLS 1.0 or TLS 1.1 will no longer connect.
✔️ Only TLS 1.2 or later will be supported.
Here’s how you can prepare your environment before the retirement:
• Review all applications and devices using POP3 or IMAP4.
• Verify they support TLS 1.2 or later.
• Update or replace clients that still rely on TLS 1.0 or 1.1.
• Confirm TLS compatibility with third-party vendors.
• Inform your helpdesk team so they’re prepared for potential connection issues during the rollout.
If all your POP and IMAP connections already use TLS 1.2 or later, no action is required.
Message ID: MC1293480