I was a Corp. Outlook moderator (I did the daily admin. processes, with close coordination with the actual admin.). We had our own Outlook server on site.
Admins can NOT see anyone's Email, or notes (etc.).
We had a Jr manager that was fired for sharing company secrets. The Outlook admin spent over a week with Outlook support trying to access the jr mngr's Email... There's no way to do it with out it being very obvious to the Email account user.
This is unbelievably wrong. It's piss easy. Assuming you don't have some sort of built in monitoring tool for HIPAA, sarbanes or PCI compliance (that retains emails, searches for keywords, etc) that gives you instant access at the click of a button and is always monitoring emails for this sort of stuff, it's unbelievably simple to do, which it should be.
If you're in Office 365, you go to the admin interface, open EAC (Exchange Admin Centre)
then click Recipients, then Mailboxes
Click Edit.
Click Mailbox Delegation
click Add, under Full access, add any account you want to have access
click Save.
Login to that account, click open mailbox, open that mailbox.
NB: you can't send as or send on behalf of unless you explicitly add those privileges, for some reason MS decided that "full access" should not be "full control"
For bonus points if you've got on prem exchange let me know and I'll walk you through it in Exchange server 2000, 2003, 2007, 2010, 2013 & 2016. Being able to do it with GUI (in powershell) is a standard Exchange server certification question, so you will need to know it if you ever want to do it.
You can also to it in lotus notes & every other email system I've ever been on the admin side, it's a basic & standard feature I honestly have no idea how you can say it can't be done. As in I'm totally baffled how anyone who reportedly works in this space can think this. I can think of multiple other ways to do it too, e.g. export the mailbox to a file & then just check the file.
Open powershell with your admin account (or any account that has the mailbox import export role, powershell to add that role:
New-ManagementRoleAssignment –Role "Mailbox Import Export" –User Administrator
Then run this command:
New-MailboxExportRequest -Mailbox [junior manager's username] -FilePath \[whatyouwantthefiletobecalled and whereyouwantit].pst
Then congrats, you've extracted it.
If it's taking awhile, run get-MailboxExportRequest to see the status
This is level 1 helpdesk stuff. You should know this if you're going to be an email admin and you definitely should not be making false claims that it can't be done. In most countries your employer has the right to read & monitor your email, it's an absolute necessity for compliance programs in numerous industries.
NEVER send anything via a work supplied email account unless you would be happy for your employer to read it. Ideally don't even use their internet or device to send it.