A piece of info which an Exchange admin checks from time to time has made it to the graphical interface in Exchange 2013 – the last time a user logged onto the mailbox.
In Exchange 2010, you have to use the shell to pull the last time the mailbox was logged onto by using the Get-MailboxStatistics cmdlet.
The same can be done in 2013, but the info can be pulled from the Exchange Administration Centre (EAC) as well. Navigate to Recipients –> Mailboxes in EAC and select the mailbox. Click on Mailbox Usage tab and there it is – last logon date and time.
If the user hasn’t logged onto the mailbox ever, a pop up window will be displayed alerting the same.
The same info is displayed in the shell as well.