Google搜索可行性：NO-------------邮件端口检测--基于oneclickvirt/portchecker开源-------------Platform  SMTP  SMTPS POP3  POP3S IMAP  IMAPSLocalPort ✔     ✔     ✔     ✔     ✔     ✔    QQ        ✘     ✔     ✘     ✘     ✘     ✘    163       ✘     ✔     ✘     ✘     ✘     ✘    Sohu      ✘     ✔     ✘     ✘     ✘     ✘    Yandex    ✘     ✔     ✘     ✘     ✘     ✘    Gmail     ✘     ✔     ✘     ✘     ✘     ✘    Outlook   ✘     ✘     ✘     ✘     ✘     ✘    Office365 ✘     ✘     ✘     ✘     ✘     ✘    Yahoo     ✘     ✔     ✘     ✘     ✘     ✘    MailCOM   ✘     ✔     ✘     ✘     ✘     ✘    MailRU    ✘     ✔     ✘     ✘     ✘     ✘    AOL       ✘     ✔     ✘     ✘     ✘     ✘    GMX       ✘     ✔     ✘     ✘     ✘     ✘    Sina      ✘     ✘     ✘     ✘     ✘     ✘    Apple     ✘     ✔     ✘     ✘     ✘     ✘    FastMail  ✘     ✔     ✘     ✘     ✘     ✘    ProtonMail✘     ✘     ✘     ✘     ✘     ✘    MXRoute   ✘     ✘     ✘     ✘     ✘     ✘    Namecrane ✘     ✔     ✘     ✘     ✘     ✘    XYAMail   ✘     ✘     ✘     ✘     ✘     ✘    ZohoMail  ✘     ✔     ✘     ✘     ✘     ✘    Inbox_eu  ✘     ✔     ✘     ✘     ✘     ✘    Free_fr   ✘     ✔     ✘     ✘     ✘     ✘    ------------------------------------------------------------------------