CmdID

CmdID / PowerShell / Cmdlets / Set

Set-MailboxIRMAccess

Use the Set-MailboxIRMAccess cmdlet to block delegate access to IRM-protected messages in other mailboxes (shared mailboxes or user mailboxes where delegates have Full Access permission). Exchange PowerShell reference

From the Exchange PowerShell reference 3 parameters Its page in the reference

Opens CmdID with your command, read as PowerShell. It is read in your browser and sent nowhere.

Parameters

3 in the Exchange PowerShell reference
-IdentityThe Identity parameter specifies the mailbox that you want to modify.
-AccessLevelThe AccessLevel parameter specifies what delegates can do to IRM-protected messages in the mailbox that's specified by the Identity parameter.
-UserThe User parameter specifies the delegate who is blocked from reading IRM-protected messages in the mailbox.