Find all Exchange mailboxes a list of users have access to with PowerShell
To find all Exchange mailboxes a list of users have access to put the mailboxes in a TXT file. One mailbox per line, e.g.: myname@domain.com mynewname@domain.com etc. Save the file as 'users.txt' and put the file on your desktop. Run this code to create a TXT file with all the mailboxes a user has access to: