I am trying to send email which I have done before but now I am using a different server and now I am getting this error - here is my code.


This is the error I am getting -

System.Net.Mail.SmtpFailedRecipientException: Mailbox unavailable. The server response was: must be authenticated
at System.Net.Mail.SmtpTransport.SendMail(MailAddress sender, MailAddressCollection recipients, String deliveryNotify, SmtpFailedRecipientException& exception)
at System.Net.Mail.SmtpClient.Send(MailMessage message)
at email_blaster.Form1.Form1_Load(Object sender, EventArgs e) in F:\email_blaster\email_blaster\Form1.vb:line 56



Any help on this would be greatly appreciated.

Do you have the ability to make a test account on the server? One that you can post the information so it can be discussed?

Although sometimes it's not easy to find, almost every ISP posts the post and protocol information, otherwise people could not connect. You need to post that. I did not intend for you to execute the code I supplied because Gmail is really wierd. What I wanted you to see was credentials presentation, port and protocol information. I doubt your ISP uses SSL and that's what my method used, so it's no wonder it doesn't work.

So you need a test accountwhere you do notneed to protectthe account for security so we can test this.

I responded to this and then thought better. Email_Blaster?

Thanks for the quick reply - but I tried that code and received the same error -

System.Net.Mail.SmtpFailedRecipientException: Mailbox unavailable. The server response was: must be authenticated
at System.Net.Mail.SmtpTransport.SendMail(MailAddress sender, MailAddressCollection recipients, String deliveryNotify, SmtpFailedRecipientException& exception)
at System.Net.Mail.SmtpClient.Send(MailMessage message)
at email_blaster.Form1.Form1_Load(Object sender, EventArgs e) in F:\email_blaster\email_blaster\Form1.vb:line 45

Do you have the ability to make a test account on the server? One that you can post the information so it can be discussed?

Although sometimes it's not easy to find, almost every ISP posts the post and protocol information, otherwise people could not connect. You need to post that. I did not intend for you to execute the code I supplied because Gmail is really wierd. What I wanted you to see was credentials presentation, port and protocol information. I doubt your ISP uses SSL and that's what my method used, so it's no wonder it doesn't work.

So you need a test accountwhere you do notneed to protectthe account for security so we can test this.

I have an exchange server with 1an1, so I could set up a test acount - I did not use the ssl part in my test and I filled in the blanks with my info - I have connected to gmail before - but this one is giving me a headache - I will post the info of the test account soon.

Good,

Then post your code along with it and we can figure it out. Make sure you can connect with Outlook. I don't think Outlook express or Windows mail is compatible with exchange?

Sorry it took forever - I was receiving an error evertime I tried to reply to this thread - antways


user - e218218362@exchange.1and1.com
pass - testertester

host - smtp.1and1.com


Thank you again

Here it is about 6 months, I no one seems to be able to post a answer to your question.

I am having the same problem, I tied you code and get the same "..authentication required..". I too, am using 1and1 or gmail or others.

QUESTION, Have you found the soution?

Thanks!

This is how I got it to work:

Imports Microsoft.VisualBasic

Imports System

Imports System.IO

Imports System.Data

Imports System.Configuration

Imports System.Web

Imports System.Web.Security

Imports System.Web.UI

Imports System.Web.UI.WebControls

Imports System.Web.UI.WebControls.WebParts

Imports System.Web.UI.HtmlControls

Imports System.Net.Mail

Imports System.Net.Mime

Imports System.Collections.Generic

Imports System.Xml

Public Class Utility

Public Shared Sub SendMail(ByVal from As String, ByVal sTo As String, ByVal subject As String, ByVal body As String)

' Declare server name

Dim mailServerName As String = "smtp.1and1.com"

' MailMessage represents the e-mail being sent

Dim message As New Net.Mail.MailMessage(from, sTo, subject, body)

' set HTML body to true

message.IsBodyHtml = True

' set client information

Dim mailClient As New Net.Mail.SmtpClient()

mailClient.Host = mailServerName

' set Username and Password for SMTP Authentication

mailClient.Credentials = New Net.NetworkCredential("user@domain.com", "password")

' send email

mailClient.Send(message)

' dispose message

message.Dispose()

End Sub

End Class

---------------------------------------------------------------------------------

MyButton looks like this:

Protected Sub btnclick(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click

Dim name As String = TextBox1.Text.Trim()

Dim comments As String = TextBox2.Text.Trim()

Dim sbMessage As New StringBuilder()

sbMessage.Append(name + " has submitted these comments on the contact us page. <br />")

sbMessage.Append("Comments: " + comments)

sbMessage.Append("<br /><br />This was sent on: " + DateTime.Now)

Utility.SendMail("sender@domain.com", "reciever@domain.com", "subject", sbMessage.ToString())

Response.Redirect("Home.aspx")

----------------------------------------------------------------------------

Hope this helps. BTW I used

What you are missing is this Smtp.EnableSsl = True, some EMails need this authentication.