My three yahoo accounts are not sending and the mails just sit in the outbox. My other email client, called EM Client, is sending the Yahoo mail without having changed any settings. As I looked I see that Yahoo settings in Zimbra Desktop cannot be edited so I cannot designate another port on which to send mail. It also will not allow me to set up the Yahoo account as a POP account and states Yahoo must be imap. Every three months it seems Yahoo goes down.