$a=get-content C:users.txt
foreach($b in $a)
{New-Mailbox -Name $b -Alias $b –Shared -PrimarySmtpAddress $b@email.org
Add-MailboxPermission $b -User me@email.com -AccessRights FullAccess -AutoMapping $true}

user1
user2

uat1
qa1
trn1
cln1

user1uat@email.org
user1qa1@email.org
user1trn1@email.org
user1cln1@email.org
user2uat@email.org
user2qa1@email.org
user2trn1@email.org
user2clan1@email.org