How to retrieve a message that has been completely deleted on a mailbox

How to retrieve a message that has been completely deleted on your mailbox, when we deleted the message and emptied the deleted item, how do we get it back, in fact, the deletion on the mailbox does not mean that the Mail on the server has been deleted, so that we can retrieve the deleted important mail from the server, We're going to have to rely on a mail client like Outlook and use it to sync our emails from the server.

First of all, we configure Outlook, this online data a lot, I believe I am not tired to mention, the mailbox server to fill in the corresponding mail business on the line, such as 163, the receiving server is pop.163.com, the sending server is smtp.163.com.

After the configuration, we will enter the Outlook mailbox, click on the menu to receive/Send the option, so that the mailbox automatically synchronized to the server mail, so that no matter you delete did not delete, all mail will be synchronized to the local, that is, retrieve the deleted mail.