Microsoft.Exchange 发邮件

//Microsoft.Exchange.WebServices.dll
ExchangeService service = new ExchangeService();

// 获取身份验证, 能够尝试你的邮箱名, 域用户ID等
// user: 登录username，邮箱登录ID或者域登录ID
// password：你懂的
// domain：域，不是域名，域用户的的话就得填这个，选填
service.Credentials = new NetworkCredential("帐号", "密码", "域名");
service.TraceEnabled = true;
service.AutodiscoverUrl("发件箱"); // 这个是发件然的邮箱地址，完整的(xx@dd.com).

EmailMessage message = new EmailMessage(service);
message.Subject = "Email的主题";
message.Body = "Email的内容";
message.ToRecipients.Add("收件箱");
message.Save();

message.SendAndSaveCopy();// 发送