asp.net - 信箱不可用。服务器响应为:访问被拒绝-无效的HELO名称(请参阅RFC2821 4.1.1.1)

我正在运行Windows Server 2008 R2，但正在收到smtp邮件异常:

信箱不可用。服务器响应为:访问被拒绝-无效的HELO名称(请参阅RFC2821 4.1.1.1)

代码隐藏:

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    Dim NewMail As New System.Net.Mail.MailMessage
    Dim str1 As String = String.Empty
    str1 = Convert.ToString(System.Configuration.ConfigurationManager.AppSettings("SmtpEmail")) '[email protected]
    Dim fromaddress As MailAddress = New MailAddress(str1)
    NewMail.From = fromaddress
    NewMail.Sender = fromaddress
    NewMail.IsBodyHtml = True
    NewMail.Subject = "TEST"
    NewMail.Body = "This is Testing..."
    NewMail.Priority = System.Net.Mail.MailPriority.Normal
    NewMail.To.Add("[email protected]")
    Dim SmtpMail As New SmtpClient()
    SmtpMail.Port = 25
    SmtpMail.Host = ConfigurationManager.AppSettings("SmtpServer").ToString 'mail.xyz.com
    SmtpMail.Send(NewMail)
    NewMail.Dispose()
    SmtpMail.Dispose()
End Sub

最佳答案

用户名或密码必须不正确，请尝试使用其他用户名和密码并将其 checkout 。}
还要验证要连接的端口(eg. 587)