Microsoft Graph
A Microsoft programmability model that exposes REST APIs and client libraries to access data on Microsoft 365 services.
12,122 questions
This browser is no longer supported.
Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support.
For identifying undelivered mail, we are checking for "report-type=delivery-status" OR "X-MS-Exchange-Message-Is-Ndr" is present or not in mail headers content. But this is not present in our undelivered mail headers