Exchange Online: Generate a Mail Read/Unread Report Using Message Trace V2 and Microsoft Graph
Need to know who actually read an internal email in Exchange Online? This approach starts with Message Trace V2 to identify who truly received the message, then uses Microsoft Graph to check the IsRead flag in each recipient mailbox via internetMessageId. The result is a practical read/unread report with a clear summary and optional CSV export without scanning every mailbox in the tenant.








