This Exchange Server 2016 article focuses on creating multiple user mailboxes with the help of CSV file and PowerShell.
Step One: Create a Users CSV File
You need to have a list of user mailboxes in CSV file. You can create a file with the help of Microsoft Excel or any notepad editor. Use the following format; the header is important.
Once the file is ready, save it with .csv extension suppose CreateMailboxes.csv.
Step Two: Import the CSV File and Creating the Mailboxes
Open PowerShell with administrative privileges and execute the following command to read the password for new user mailboxes.
$Password=Read-Host “Enter Password” –AsSecureString
When you are done reading the password, create user mailboxes with the help of following command.
You are done.