The email terms trash and message junk refer to unsolicited messages, not deseadoso with sender unknown (anonymous mail), normally containing advertising are generally shipped in large quantities (even mass) that damage of one or several ways to receiver.
It requires or needs the emails sent or received by a reliable email address not go directly to the tray unwanted emails or spam, for this process to be performed which is called as Add safe sender.
When you send a message to a person or organization that is not a contact in Outlook, the e-mail recipient is not added to the Safe Senders List by default. This means that when a recipient responds to your message, the reply message is moved to the Junk E-mail folder.
To ensure that the message recipients, although not Outlook contacts are in the Safe Senders List, do the after: