c# - 使用ZOHO SMTP配置发送邮件时出现`The operation has timed out.`异常

Question

我正在使用 ZOHO用于通过我的应用程序发送邮件的邮件服务器。但是它无法连接到服务器并抛出异常The operation has timed out.。以下是我的代码:

public int sendMail(string from, string to, string subject, string messageBody) {
    try {
        SmtpClient client = new SmtpClient();
        client.Port = 465;
        client.Host = "smtp.zoho.com";
        client.EnableSsl = true;
        client.Timeout = 10000;
        client.DeliveryMethod = SmtpDeliveryMethod.Network;
        client.UseDefaultCredentials = false;
        client.Credentials = new System.Net.NetworkCredential(Username, Password);

        MailMessage mm = new MailMessage(from, to, subject, messageBody);
        mm.BodyEncoding = UTF8Encoding.UTF8;
        mm.IsBodyHtml = true;
        mm.DeliveryNotificationOptions = DeliveryNotificationOptions.OnFailure;

        client.Send(mm);
        return 0;
    } catch (Exception) {
        throw;
    }
}

我还尝试按照此处的建议使用端口 587 Send email using smtp but operation timed out using ZOHO .但问题仍然存在。

Zoho SMTP 配置帮助链接:https://www.zoho.com/mail/help/zoho-smtp.html

Answer 1

超时问题通常与网络、端口问题有关，我没有使用 SSL 或 TLS 方法发送电子邮件的经验，但我也会检查一下，当然我假设你在尝试 TLS 时更改了端口号.