The total or singular mailbox storage limit based on the “Prohibit send receive quota.” The “Prohibit send receive quota (MB) refers to the storage limit when the mailbox can no longer send or receive emails. If your organization’s policies prevents you from viewing reports where user information is identifiable, you can change the privacy setting for all these reports. Check out the Hide user details in the reports section in the Activity Reports in the Microsoft 365 admin center.
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