This article explains why emails sent using the Microsoft 365 (M365) email provider do not appear in the mailbox Sent Items folder and outlines the available resolution. This situation occurs when utilizing the built-in Branding email provider configuration for out-of-the-box email templates.

• Microsoft 365
• Email Provider
• Microsoft Graph API

The pre-built M365 email provider integration is designed for a standardized configuration and does not currently expose or enable the saveToSentItems flag internally. Because this flag is not set to true by default within the out-of-the-box integration, messages are not saved to the Sent Items folder.

To gain control over the email payload and ensure messages are saved to the Sent Items folder, a custom integration is required.

• Configure a Custom Email Provider to replace the out-of-the-box M365 provider.

• Use the Custom Email Provider to send emails via the Microsoft Graph API.

• Explicitly set the saveToSentItems property to true within the API payload.

NOTE: For assistance with Azure-side configurations that might globally enforce this flag, contact the Azure Team.

Related References 

• Submit product feedback to request this feature for the Microsoft 365 Email Provider.