Details:
If you are going to use your existing e-mail account as a mail forwarder or mailing
list, you are recommended to switch off the mailbox service: a mailbox keeps all
incoming messages and messages are not removed automatically after being
forwarded. Therefore, if you choose to have the "mailbox + mail forwarder"
configuration on your account, be sure to clean up the mailbox from time to time.
To switch off the mailbox service for your account discarding all messages in
your mailbox:
1 On your Home page, click the domain name you need.
2 Click the Mail icon.
3 Click the required e-mail address.
4 Click the Mailbox icon in the Tools group.
5 Deselect the Mailbox check box.
6 Click OK.