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Access the Mailboxes page as explained in Mailboxes
Click New Mailbox. The page changes to let you configure a new mailbox. Enter the following information.
Name: The name used to identify the mailbox
Mailbox Type: Choose POP3 or IMAP
Host: The host URL. For example, pop.3.gmail.com
Port: 110 by default. Your mail provider can issue a different port
Account: The email address you’re creating. For example, JDoe@gmail.com
Password: The password required to access the mailbox
SSL Enabled: Choose No to disable SSL or Yes to enable it.
SSL encrypts all data exchanged between the client's mail client and your mail server with a digital security certificate to protect your password and messages. Your email provider determines whether encryption is required.Status: The mailbox status. Choose Active if the mailbox is currently in use or Not Active is the mailbox is not in use
Comments: A brief description of the purpose of the mailbox, or other relevant information
Oauth Enabled: Appears if you choose IMAP as your Mailbox Type. Choose Yes if your mailbox has open authentication enabled or No if it doesn’t
Oauth Provider: Appears if you choose Yes for Oauth Enabled. Select the protocol enabling your open authentication: Unknown, Gmail, or Office365.
If you pick Gmail, enter the Client ID, Client Secret, and Refresh Token needed for this protocol
If you pick Office365, you need to choose the Authentication Method first--API Username/Password or Client Secret, then complete the information in the boxes that appear.
API Username/Password: Enter the Client ID and Tenant ID needed for this protocol
Client Secret: Enter the Client ID, Tenant ID, and Client Secret needed for this protocol
Click OK when done. The new mailbox appears in the Mailboxes page
