@Paul Chen - ACP Thank you for reaching out to us, As I understand you are getting 403 error while accessing Azure AD blade.
Would like to know what kind of privileges/roles you have ?
This error (403) typically means the admin of the tenant has not given the permission to access the "Admin Portal" with a non-administrator account.
Refer to this article - https://learn.microsoft.com/en-us/azure/active-directory/fundamentals/users-default-permissions which talks about the kind of permissions a user has and type of restrictions admin can apply within the Azure AD to restrict access.
Would recommend to check with your Global admin to check what kind of access your account has ?
Let me know if you have any further questions, feel free to post back.
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