http://exchangepedia.com/blog/2006/12/bulk-mailbox-enabling-users-exchange-shell.html
get-user –organizationalUnit people | where-object {$_.RecipientType –eq “User” -and $_.department –eq “Sales”} | Enable-Mailbox –Database “EXCHANGE1\Mailbox Database” | get-mailbox | select name,windowsemailaddress,database
Имейте чтение через первой ссылки - очень полезный.