Free Personal Microsoft Outlook accounts no longer work with API v2
Incident Report for Nylas
Monitoring
Microsoft has disabled Basic (Non-OAuth) authentication for Exchange Online mailboxes using Free or Family licenses - also known as Personal Accounts. These include free email addresses using the domains outlook.com, hotmail.com, live.com, msn.com, and others.

Microsoft only allows these mailboxes to use Exchange Web Services and Exchange ActiveSync using Basic authentication, so these mailboxes are no longer able to utilize those services. Our API v2 uses both of those services to communicate with all Microsoft mailboxes.

Microsoft has provided no work-around for continuing to use those services, so these mailboxes can no longer use our API v2 and must start using our API v3. We use Microsoft Graph API for our API v3 and that is not affected.

This does NOT affect paid mailboxes using Microsoft's Business or School licenses. This also does NOT affect on-premise Exchange mailboxes. Only free mailboxes using Microsoft's Free or Family licenses are affected.
Posted Oct 01, 2024 - 13:09 PDT
This incident affects: 3rd Party Providers (Outlook.com).