Microsoft is reporting authentication issues for users that may impact a small fraction of Nylas users
Incident Report for Nylas
Microsoft has re-opened a previous incident for an issue that is affecting third party connections to a small number of mailboxes and other free Microsoft email accounts (link to their status page is below).

This issue can cause Nylas accounts connected to these mailboxes to abruptly go invalid and require re-authentication to continue. Our system automatically retries the credentials before setting accounts Invalid, but Microsoft's servers are still incorrectly rejecting them at times. This has been occurring sporadically since late January.

Until Microsoft resolves this issue, our recommended work-around is to ensure that the users are authenticating these accounts with App Passwords and re-authenticate when the Nylas account goes Invalid.

More information:
Posted Feb 20, 2024 - 13:09 PST
This incident affects: 3rd Party Providers (