When collaborating with external partners, you likely create B2B guest accounts in your tenant, inviting them via Entra ID or adding them to your Teams in Microsoft Teams. However, when partner companies change their email domains, such as rebranding their primary domain, you might encounter issues where email messages cannot be sent, resulting in non-delivery notifications even when using the new correct email address.

In this session, you will learn about the reasons behind this by-design behavior of Entra ID and how to resolve it within your tenant. We will explore the technical details and provide practical solutions to ensure seamless communication with your external partners despite domain changes.