Hi @A Ska ,
Your command will search for send events for all mailboxes, I recommend adding a sender condition.
For example:
$msgs= Get-TransportServer | Get-MessageTrackingLog -Start "01/23/2023 00:00:00" -End "01/23/2023 23:59:59" -ResultSize unlimited -Sender "user@contoso.com" | where{$_.EventId -LIKE "SEND*"}
$msgs.count
Or you can search the total number of sent items by selecting the sent time in the search box in Outlook client:
1. click sent items and click search box with option “current folder”
2. Click the drop-down list and select the SENT condition (if not, click Add more options to add)
3. Then there is an items in the lower left corner of the client, showing the total count.
(This will include all outgoing messages, including meeting invitations and rejected messages.)
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