Which RBAC role must be assigned to session hosts to use MSIX app attach with an Azure Storage account?

The correct RBAC role that must be assigned to session hosts to use MSIX app attach with an Azure Storage account is the Storage Blob Data Contributor. This role grants the necessary permissions to create, delete, and update blobs, which is essential for managing and accessing the MSIX packages stored in Azure Blob Storage.

When using MSIX app attach, applications are delivered to users dynamically through MSIX packages stored in an Azure Storage account. The Storage Blob Data Contributor role provides full access to the data in the blob storage, allowing session hosts to read and write the MSIX packages, ensuring that they can install and run the applications properly in a virtual desktop environment.

The other choices do not provide the complete set of permissions needed for MSIX app attach. The Storage Blob Data Reader role would only grant read access, lacking the ability to modify or update content, which is critical for deploying and managing applications effectively. The Storage File Data SMB Share Contributor and Storage File Data SMB Share Reader roles pertain specifically to file shares within Azure Storage, which are not used for managing blobs required for MSIX app attach. Thus, only the Storage Blob Data Contributor role is suitable for this scenario.