Dev guide / Provider guides / Microsoft / Microsoft Troubleshooting / Troubleshoot Microsoft authentication Troubleshoot Microsoft authentication ⛔️ As of October 1, 2022, Microsoft has deprecated Basic authentication support for all Exchange Online accounts. For more information, see Nylas' Microsoft Exchange Online Basic authentication changes guide. Nylas Was Unable to Connect to the Exchange Server Couldn't Exchange OAuth Code for a Microsoft Refresh Token Exchange Autodiscovery Failed Incorrect Connection Settings Credential Errors Not Related to a Password Invalid Password Error Status 403 Unauthorized Error