Question

所以我试图通过VB.net代码发送电子邮件，我不断收到此错误。我已经禁用了我的防火墙，并且当它没有从文本框中获取文本时我可以成功发送电子邮件。我知道我有正确的设置，因为当我发送一行主体的电子邮件时它会起作用。

Private Sub SendMessage(ByVal SmtpHost As String, ByVal SmtpPort As Integer, ByVal ssl As Boolean, ByVal SmtpUsername As String, ByVal SmtpPassword As String, ByVal mail_from As String, ByVal display_name As String, ByVal Send_To As String, ByVal subject As String, ByVal Body As String, Optional ByVal Attachments As String() = Nothing)
        Using smtp As New SmtpClient
            smtp.Host = SmtpHost
            smtp.Port = SmtpPort
            smtp.UseDefaultCredentials = False
            smtp.Credentials = New Net.NetworkCredential(SmtpUsername, SmtpPassword)
            smtp.EnableSsl = ssl

            Dim message As New MailMessage()
            Try
                message.From = New MailAddress(mail_from, display_name, System.Text.Encoding.UTF8)
                message.To.Add(Send_To)
                message.Subject = subject
                message.Body = Body
                If Attachments IsNot Nothing Then
                    For Each attachment As String In Attachments
                        message.Attachments.Add(New Attachment(attachment))
                    Next
                End If
                message.ReplyToList.Add(New MailAddress(mail_from))

                smtp.Send(message)
            Catch ex As Exception
                Debug.WriteLine(ex)
            End Try
        End Using

错误：

System.Net.Mail.SmtpException: Failure sending mail. ---> System.Net.WebException: Unable to connect to the remote server ---> System.Net.Sockets.SocketException: A socket operation was attempted to an unreachable network 0.0.0.1:465
   at System.Net.Sockets.Socket.DoConnect(EndPoint endPointSnapshot, SocketAddress socketAddress)
   at System.Net.ServicePoint.ConnectSocketInternal(Boolean connectFailure, Socket s4, Socket s6, Socket& socket, IPAddress& address, ConnectSocketState state, IAsyncResult asyncResult, Exception& exception)
   --- End of inner exception stack trace ---
   at System.Net.ServicePoint.GetConnection(PooledStream PooledStream, Object owner, Boolean async, IPAddress& address, Socket& abortSocket, Socket& abortSocket6)
   at System.Net.PooledStream.Activate(Object owningObject, Boolean async, GeneralAsyncDelegate asyncCallback)
   at System.Net.ConnectionPool.GetConnection(Object owningObject, GeneralAsyncDelegate asyncCallback, Int32 creationTimeout)
   at System.Net.Mail.SmtpConnection.GetConnection(ServicePoint servicePoint)
   at System.Net.Mail.SmtpClient.Send(MailMessage message)
   --- End of inner exception stack trace ---
   at System.Net.Mail.SmtpClient.Send(MailMessage message)
   at EmailSender.Form1.Timer2_Tick(Object sender, EventArgs e)

Answer 1

您的代码可能没有任何错误。但是这个具体的“发送邮件失败”是如果您的邮件帐户配置不正确，则会出现您必须允许访问第三方或外部应用程序才能使用您的邮件的SMTP服务。您可以在邮件设置中更改它。

改变并尝试。这可能有用。

Answer 2

Try
Dim mMailMessage As MailMessage = New System.Net.Mail.MailMessage()
Dim fromEmail As String = "<sender_mail_ID"
Dim fromPW As String = "<sender_password>"
Dim toEmail As String = "<Receiver_mail_ID>"
mMailMessage.From = New MailAddress(fromEmail)
mMailMessage.[To].Add(toEmail)
mMailMessage.Subject = "<Subject goes here>"
mMailMessage.Body = "<Message AKA Body goes here>"
mMailMessage.DeliveryNotificationOptions = DeliveryNotificationOptions.OnFailure

Dim smtpClient As New SmtpClient("smtp.gmail.com", 587)
smtpClient.EnableSsl = True
smtpClient.DeliveryMethod = SmtpDeliveryMethod.Network
smtpClient.UseDefaultCredentials = False
smtpClient.Credentials = New NetworkCredential(fromEmail, fromPW)

smtpClient.Send(mMailMessage.From.ToString(), mMailMessage.[To].ToString(), mMailMessage.Subject, mMailMessage.Body)

Catch ex As Exception

End Try

不要忘记使用：

Imports System.Net.Mail
Imports System.Net

Answer 3

我的2美分。在我的情况下，我把所有东西都完美地布置了，什么东西把我扔了，却没有意识到我在后台运行了privateinternetaccess应用程序，阻止了每次连接到服务器的尝试。不酷：（

邮件发送失败。无法连接到远程服务器。套接字操作

3 个答案: