Hi @Ben Cary ,
As Troy said, you could use Search-Mailbox to find these mails and use -DeleteContent to delete them:
Delete received messages:
Search-Mailbox -Identity User01 -SearchQuery ‘Received<01/01/2021’ -DeleteContent.
Delete Sent messages:
Search-Mailbox -Identity User01 -SearchQuery ‘Sent<01/01/2021’ -DeleteContent
Note these cmdlets will permanently delete these messages, they won’t go to the recovery items folder.
Regards,
Lou
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