Error: need EHLO and AUTH first-详细内容

文章内容

2019/9/3 15:42:56,作者: 黄兵

Error: need EHLO and AUTH first

今天通过System.Net.Mail的时候出现了如下错误：

Error: need EHLO and AUTH first

1、启用smtp.UseDefaultCredentials = true;

2、启用smtp.EnableSsl = true;

同时端口是587，并不是官方所说的465。

具体代码如下：

using Microsoft.AspNetCore.Identity.UI.Services;
using Microsoft.Extensions.Options;
using System.Text;
using System.Threading.Tasks;
using System.Net.Mail;
using System.Net;

namespace QuickstartIdentityServer.Services
{
    public class EmailSender:IEmailSender
    {
        public EmailSender(IOptions<AuthMessageSenderOptions> optionsAccessor)
        {
            Options = optionsAccessor.Value;
        }

        public AuthMessageSenderOptions Options { get; } //set only via Secret Manager

        public Task SendEmailAsync(string email, string subject, string message)
        {
            return Execute(Options.SmtpUser,Options.SmtpPassword, subject, message, email);
        }

        public Task Execute(string SMTP_User,string SMTP_Pass, string subject, string message, string email)
        {
            SmtpClient client = new SmtpClient();
            client.Host = "smtp.exmail.qq.com";
            client.Port = 587;
            client.UseDefaultCredentials = true;
            client.DeliveryMethod = SmtpDeliveryMethod.Network;
            client.EnableSsl = true;
            client.Credentials = new NetworkCredential(SMTP_User + "@pdflibr.com", SMTP_Pass);

            MailMessage Message = new MailMessage();
            Message.From = new MailAddress(SMTP_User + "@pdflibr.com");
            Message.To.Add(email);
            Message.Subject = subject;
            Message.Body = message;
            Message.BodyEncoding = Encoding.UTF8;
            Message.Priority = MailPriority.High;
            Message.IsBodyHtml = true;

            return client.SendMailAsync(Message);           
        }
    }
}