The server specified in the SmtpServer property is not valid or not available

Is a valid SMTP Server
Check to be sure the server System.Web.Mail is executing on can connect to the mail server. Some times firewalls or proxy servers can get in the way.
Try specifying the value by IP address. Poor DNS resolution can sometimes hinder name lookups.
Make sure the that the mail server is running at port 25

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SMTP Server Error [ Reply ]
I am sending mail with my local smtp server. it goes from outlook express without any error. but mail are going at destination mail id. when i check the system log, there was a warning message that stating
"Message delivery to the remote domain 'yahoo.com' failed for the following reason: Destination server does not exist."
my machine is connected to internet through LAN and DNS client service running.

Rajaram [ rajaram dot vijayvergiya ( at ) cistemsindia dot com ], 2005-02-28 06:47:41 #
- RE: SMTP Server Error [ Reply ]
  What is my SMTP for AOL out going and incomming I would like to try out look as my email and I am trying to set it up?
  
  Dean [ dcgambino ( at ) aol dot com ], 2005-11-05 08:28:35 #
- RE: SMTP Server Error [ Reply ]
  cant log in plenty of fish
  
  steven younger [ steven_younger ( at ) sky dot com ], 2010-08-09 08:50:51 #
problem in sending mail [ Reply ]
hello,

i am trying to send email in asp.net using smtp server but its giving error message as.

COMException (0x8004020f): The server rejected one or more recipient addresses. The server response was: 550 5.7.1 Unable to relay for tanuja.anupalli@gmail.com

my code is as follows:

msg=new MailMessage();
msg.Priority=MailPriority.High;
msg.From="tmythilee@yahoo.com";
msg.To="tanuja.anupalli@gmail.com";
msg.Cc="mythileereddy@yahoo.com";
msg.Subject="Hello";
System.Web.Mail.SmtpMail.SmtpServer="localhost";
SmtpMail.Send(msg);

plese kindly help me in this.

tanuja [ tmythilee ( at ) yahoo dot com ], 2005-05-16 22:08:03 #
- RE: problem in sending mail [ Reply ]
  
  Dear... your code is absolutely right.
  
  you should do one thing.. go thru this
  
  settings---->controlpanel-->administrative tools-->iis--->default smtp virtual server--->properties---->access----->relay---->only the list below---->Add----->127.0.0.1(default ip)
  
  And try.. it must be runnn..........
  
  Saurabh Nayak [ whysaurabh ( at ) yahoo dot com ], 2005-11-28 02:43:59 #
  - RE RE: problem in sending mail [ Reply ]
    i am using smtp server to send mail but it has shown (The transport failed to connect to the server )this message
    
    anbarasu [ anbu_14 ( at ) yahoo dot com ], 2008-03-05 03:40:26 #
out going mail problem [ Reply ]
my linux mail server is configured with sqirrel mail and working fine. After some time it is not able to sending the mails. The server message is as follows : Server replied 550 relaying, prohibited by adminstrator .

what would be the solution

raju [ hydedp ( at ) scclmines dot com ], 2005-06-13 01:34:28 #
- RE: out going mail problem [ Reply ]
  Hello,
  
  how can i identify this email id is valid or not.
  means email id is currntly in use or not. if i send an email through my then it send failure delivery to me. Before sending a email i want to check this email id is valid or not. Please help me.
  
  sachin Patil [ sachin_hin2003 ( at ) yahoo dot co dot in ], 2007-04-06 23:09:56 #
- RE: out going mail problem [ Reply ]
  i can be able to receive e-mails but i can't send them. can you please help
  
  jacob [ japonym ( at ) webmail dot co dot za ], 2011-02-01 22:28:55 #
550 not local host yahoo.com, not a gateway [ Reply ]
I am able to receive mails but not able to send them. Pls help. Thank you

sanjay [ sanjay ( at ) orion-tec dot com ], 2006-05-03 21:58:06 #
error for sending mail [ Reply ]
The server rejected one or more recipient addresses. The server response was: 550 5.7.1 ,asp.net

kalu [ kaluahir16 ( at ) yahoo dot co dot in ], 2007-01-31 03:18:08 #
- RE: error for sending mail [ Reply ]
  The message could not be sent because connecting to SMTP server smtpout.secureserver.net failed. The server may be unavailable or is refusing SMTP connections. Please verify that your SMTP server setting is correct and try again, or else contact your network administrator.
  
  Thanks,
  
  Kay Harrison [ kay ( at ) csmarketing dot org ], 2009-09-25 07:00:07 #
error for sending mail [ Reply ]
The server rejected one or more recipient addresses. The server response was: 550 5.7.1 ,asp.net

kalu [ kaluahir16 ( at ) yahoo dot co dot in ], 2007-01-31 03:18:22 #
smtp server ip address? [ Reply ]
How do I find the IP address of my smtp server? Thanks!

mrees [ mrees515 ( at ) gmail dot com ], 2007-02-21 13:22:03 #
SmtpServer [ Reply ]
Question,

The code is a rather simple automated email.
It works fine on the local intranet with the given external SmtpServer.
It comes up with the following error message when running on the actual Web Host's Server.
Error number 504
- need fully qualified hostname -
The mail SmtpServer is on a different server than the Web Host.
Any ideal?

Tom [ cosmopolitanstudios ( at ) mail2me dot com dot au ], 2007-04-05 22:46:02 #
550, local host gmail.com,not gatway [ Reply ]
550, local host gmail.com,not gatway

bora [ bora_ourng2003 ( at ) yahoo dot com ], 2007-07-18 20:51:01 #
SMTP mail sending error [ Reply ]
Hi,

I am getting the below message while sending emails from asp.net 1.1 using SMTP (Webmail).

If somebody can help its really great.

"System.Web.HttpException: Could not access 'CDO.Message' object. ---> System.Reflection.TargetInvocationException:
Exception has been thrown by the target of an invocation. --->
system.Runtime.InteropServices.COMException (0x80040211): The message could not be sent to the SMTP server.
The transport error code was 0x800ccc15. The server response was not available

Thanks.

Romit [ romitkhanna ( at ) gmail dot com ], 2008-02-06 10:40:25 #
- RE: SMTP mail sending error [ Reply ]
  Hi,
  According to the error, System.Web.Mail cannot get a response back from your mail server.
  
  Just for grins, from the same server using System.Web.Mail, if possible, you may want to try telnetting to your SMTP server, to see if you can establish a connection.
  
  Cheers!
  Dave
  
  dave wanta [ dave ( at ) advancedintellect dot com ], 2008-02-06 10:50:44 #
on smtp server [ Reply ]
protected void Button3_Click(object sender, EventArgs e)
{
SmtpMail.SmtpServer ="203.199.109.167";

MailMessage mail = new MailMessage();
mail.To = "support@mastercomputech.com";
mail.From = "support@mastercomputech.com";
mail.Subject = "send";
mail.Body = "Hello";
// mail.Fields="
mail.Fields["http://schemas.microsoft.com/cdo/configuration/smtpserverport";] = 25;
mail.Fields["http://schemas.microsoft.com/cdo/configuration/sendusing";] = 2;
mail.Fields["http://schemas.microsoft.com/cdo/configuration/smtpauthenticate";] = 1;
mail.Fields["http://schemas.microsoft.com/cdo/configuration/sendusername";] = "username";
mail.Fields["http://schemas.microsoft.com/cdo/configuration/sendpassword";] = "password";
mail.Fields["http://schemas.microsoft.com/cdo/configuration/smtpusessl";]= "true";
//SmtpMail.SmtpServer = "mastercomputech.com";
SmtpMail.Send(mail);

// SmtpMail.Send(mail);
Label1.Text = "sent";
}

sushree [ ssnayak5 ( at ) rediffmail dot com ], 2008-04-15 06:24:52 #
- RE: on smtp server [ Reply ]
  test
  
  ddd [ janmoosic ( at ) hotmail dot com ], 2008-06-06 04:40:27 #
Send Mail is'nt receiving at destination [ Reply ]
I am using localhost as SMTPmail.SmtpServer ,i have already set the IIS SMTP Virtual server properties (IP address as 127.0.0.1), but at destination i am not reciving any mail,while i am not facing any type of problem because i have already solved all of them.

Manav [ v dot vend ( at ) rediffmail dot com ], 2008-09-24 04:48:05 #
error on send mail from my server [ Reply ]
i have an contactus form.there i want to send a mail to specific mail ids...so i am using smtp server

SmtpMail.SmtpServer = "smtpout.secureserver.net";

error msg is showing

The transport failed to connect to the server.

can any one tell me what would be correct smtp server address????

Bibek Barai [ webwave dot bibek ( at ) gmail dot com ], 2009-07-02 11:15:45 #
SmtpMail.SmtpServer problem [ Reply ]
i m getting this error if i set SmtpMail.SmtpServer="mail.mydomain.com"
but if i do it on my local pc to check wether mails are going or not using
SmtpMail.SmtpServer="" then its working fine....

i want to upload my files on my server....then what settings or what what shoud i do?

should i keep it like SmtpMail.SmtpServer="" or
SmtpMail.SmtpServer="mail.mydomain.com"

i need help very urgently....
can any one help me to tell what should i do to resolve this problem?

The server rejected one or more recipient addresses. The server response was: 550 not local host yahoo.co.in, not a gateway

Kiran [ ksp_852005 ( at ) yahoo dot co dot in ], 2010-04-03 02:24:05 #

	System.Web.Mail, OH MY!
	Complete FAQ for sending email in ASP.NET (or trying to) with System.Web.Mail
	If you are using .NET 2.0 be sure to check out my System.Net.Mail site