Can a user exist in mail enabled security in graph and service account in exchange online?

Hi, @Mukesh Kumar

Yes, users can belong to both a service account and a mail-enabled security group, whilst also having basic read permissions to ensure that applications have unrestricted access to the user's data. To ensure that applications have unrestricted access to a user's data, service accounts can be assigned the necessary read permissions. This can be done through the Microsoft Graph API.

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