i'm writing a C# email application which is currently being designed for use with Gmail so I can test authentication. However I'm getting an error which doesn't seem to make much sense as I am setting SSL to true and using a user and password.
Error Message:
System.Net.Mail.SmtpException: 'The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required. Learn more at'
using System;
using System.Net;
using System.Net.Mail;
namespace EmailSendingProgram
{
public class EmailSendingClass
{
public static void Main(string[] args)
{
Console.WriteLine("Type your Gmail Address: ");
string from = Console.ReadLine();
Console.WriteLine("Type your Gmail Password: ");
string password = Console.ReadLine();
Console.WriteLine("Type the Email Address you wish to send to: ");
string to = Console.ReadLine();
Console.WriteLine("Type the Subject of the email: ");
string subject = Console.ReadLine();
Console.WriteLine("Type or paste in your email (either text or HTML): ");
string body = Console.ReadLine();
EmailSendingClass email = new EmailSendingClass();
email.Send(from, password, to, subject, body);
}
/// handles sending the email
/// hardcoded to work with gmail just change the CreateSmtpClient from
/// "smtp.gmail.com", 587 to whatever you want to use
public void Send(string from, string password, string to, string subject, string body)
{
var message = CreateMailMessage(from, to, subject, body);
// Host and Port setup for use with Gmail
using (SmtpClient client = CreateSmtpClient("smtp.gmail.com", 587, from, password))
{
client.Send(message);
}
}
/// Defines the SmtpClient for the mail message
/// setups up the network credentials to send the email
private SmtpClient CreateSmtpClient(string host, int port, string from, string password)
{
SmtpClient client = null;
client = new SmtpClient()
{
Host = host,
Port = port,
EnableSsl = true,
Credentials = new NetworkCredential(from, password)
};
return client;
}
/// defines what is contained in the email and where it will be sent
/// also makes all messages send as HTML
private MailMessage CreateMailMessage(string from, string to, string subject, string body)
{
MailMessage message = null;
message = new MailMessage(from, to)
{
Subject = subject,
Body = body
};
message.IsBodyHtml = true;
return message;
}
}
}
I understand that something is being done incorrectly with the authentication but I can't seem to figure out what specifically. So any help would be appreciated.
I encountered a similar problem caused by TLS 1.2 support issues. If this is your case, the simplest solution might be to target .NET 4.6.1 or higher. Other suggestions can be found here and here.
The issue wasn't the program but rather was Gmail refusing sign in from "less secure apps"
I simply clicked the secure your account button and allowed this account to be signed in from less secure apps.
Related
I.m working on a Windows app where the user has to enter a password. I also have a "Forgot Password" link. on the window. When that's clicked, I have the user enter their email address and click a Submit button. Every time they enter an email address and click the button, I get the error message:
SmtpException has occured: The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.7.0 Authentication Required.
The code I'm using is:
try
{
Cursor = Cursors.WaitCursor;
MailAddress from = new MailAddress("bgatt64#gmail.com", "Bob Gatto");
MailAddress to = new MailAddress("bgatto64#yahoo.com", "Bob Gatto");
MailMessage eMsg = new MailMessage(from, to);
eMsg.Subject = "Your Password Renewal Request";
eMsg.IsBodyHtml = true;
eMsg.Body = "This is the body.";
SmtpClient eClient = new SmtpClient("smtp.gmail.com", 587);
eClient.EnableSsl = true;
eClient.UseDefaultCredentials = true;gmail
// The following email and password used is that of my own gmail email
// that I use for my own personal email.
eClient.Credentials = new System.Net.NetworkCredential("<MyOwnEmail#gmail.com>", "<MyPassword>");
eClient.Send(eMsg);
}
catch (SmtpException ex)
{
throw new ApplicationException("SmtpException has occurred: " + ex.Message);
}
catch (Exception ex)
{
throw ex;
}
What else needs to be done?
You cannot use your plain google account password to authenticate to Gmail SMTP server anymore as Google requires two-step authentication now.
You'll need to use the App Password instead:
Go to https://myaccount.google.com/security and turn on Two Step verification
Click "App Passwords"
Request a new password for the Mail application on the Windows Computer
You'll get the string with the 4 groups of characters. Now you need to use it in your code:
eClient.Credentials = new System.Net.NetworkCredential("<MyOwnEmail#gmail.com>", "<App Password>");
You can find more info Here
After the removal of less secure apps you can no longer use your actual google password to connect to the smpt server you need to create an apps password.
How to create a Apps Password for connecting to Google's SMTP server.
using System;
using System.Net;
using System.Net.Mail;
namespace GmailSmtpConsoleApp
{
class Program
{
private const string To = "[redacted]#gmail.com";
private const string From = "[redacted]#gmail.com";
private const string GoogleAppPassword = "";
private const string Subject = "Test email";
private const string Body = "<h1>Hello</h1>";
static void Main(string[] args)
{
Console.WriteLine("Hello World!");
var smtpClient = new SmtpClient("smtp.gmail.com")
{
Port = 587,
Credentials = new NetworkCredential(From , GoogleAppPassword),
EnableSsl = true,
};
var mailMessage = new MailMessage
{
From = new MailAddress(From),
Subject = Subject,
Body = Body,
IsBodyHtml = true,
};
mailMessage.To.Add(To);
smtpClient.Send(mailMessage);
}
}
}
Note: if you are trying to connect users then you could also use Xoauth2 but using an apps password is far easer solution.
I am having an issue with SmtpClient in an ASP.NET web application.
I have a generic function that builds an email message and then sends it. The code is as follows:
public static bool SendMessage( string fromName, string toName, string subject, string body ) {
var smtpClient = new SmtpClient("server address here")
{
Port = 587,
Credentials = new NetworkCredential("user", "pass"),
EnableSsl = false,
};
var mailMessage = new MailMessage
{
From = new MailAddress("sender", "Testing"),
Subject = subject,
Body = body
};
mailMessage.To.Add ( new MailAddress(toName, "Valued Customer") );
try {
smtpClient.Send ( mailMessage );
return true;
}
catch (Exception ex) {
var error = $"ERROR :{ex.Message}";
return false;
}
}
The problem is, I get the following error when I call it:
Mailbox unavailable. The server response was: <email address being sent to> No such user here
Naturally I removed the value in the < >, but in the original error message it is the email address of the recipient. I almost think the SMTP server believes the recipient has to be a user on the system.
What can I try next? I even hard-coded email addresses in rather than using variables, thinking maybe there was some weird issue with that, but it didn't work.
The error is telling you that the the SMTP server does not have a user with that email address (usually it has to do with security around the FROM address). The SMTP server will not send email if it does not recognize the FROM address.
Solution, change your FROM. Example:
var mailMessage = new MailMessage
{
From = new MailAddress("tester", "test#adminsystem.com"),
Subject = subject,
Body = body
};
I have been working on this project to send an e-mail to a user and I have had an error come up all the time. (I'm using the EASendMail NuGet package) It is "The type initializer for '?' threw an exception." (this is in the console for the error system that the package has) I dont really know what that means, my code is this:
using EASendMail;
namespace Email
{
class Program
{
static void Main(string[] args)
{
try
{
SmtpMail oMail = new SmtpMail("TryIt");
// Set sender email address, please change it to yours
oMail.From = "Splat2ooner#gmail.com";
// Set recipient email address, please change it to yours
oMail.To = "Splat2ooner#gmail.com";
// Set email subject
oMail.Subject = "test email from c# project";
// Set email body
oMail.TextBody = "this is a test email sent from c# project, do not reply";
// SMTP server address
SmtpServer oServer = new SmtpServer("smtp.gmail.com");
// User and password for ESMTP authentication
oServer.User = "Splat2ooner#gmail.com";
oServer.Password = "password (not my passoword)";
// Most mordern SMTP servers require SSL/TLS connection now.
// ConnectTryTLS means if server supports SSL/TLS, SSL/TLS will be used automatically.
oServer.ConnectType = SmtpConnectType.ConnectTryTLS;
// If your SMTP server uses 587 port
//oServer.Port = 587;
// If your SMTP server requires SSL/TLS connection on 25/587/465 port
//oServer.Port = 25; // 25 or 587 or 465
oServer.ConnectType = SmtpConnectType.ConnectSSLAuto;
Console.WriteLine("start to send email ...");
SmtpClient oSmtp = new SmtpClient();
oSmtp.SendMail(oServer, oMail);
Console.WriteLine("email was sent successfully!");
}
catch (Exception ep)
{
Console.WriteLine("failed to send email with the following error:");
Console.WriteLine(ep.Message);
}
}
}
}
Thanks.
It looks like newer version of "EASendMail" (as of now the latest version is 7.5.0.3) package has this issue.
I don't have much time to do research on it, just installed older version (7.3.1.2) and it resolved this.
hope it helps.
I am running an ASP.Net application on windows azure and I need to send an email from it. I am trying to send it using my gmail account as follows, however when I attempt to send it, I get the following error:
The SMTP server requires a secure connection or the client was not
authenticated. The server response was: 5.5.1 Authentication Required.
Learn more at
The code:
private static readonly string EMAIL_ADDRESS = "mymail#gmail.com";
private static readonly string EMAIL_FROM = "MY FROM NAME";
private static readonly string EMAIL_PASS = "my Password";
private static readonly string EMAIL_HOST = "smtp.gmail.com";
private static readonly int EMAIL_PORT = 587;
private static readonly bool EMAIL_SSL = true;
private static readonly SmtpDeliveryMethod EMAIL_DELIVERY_METHOD = SmtpDeliveryMethod.Network;
private static readonly bool EMAIL_DEFAULT_CREDENTIALS = false;
public static void SendEmail(string recipientEmail, string subject, string body) {
var fromAddress = new MailAddress(EMAIL_ADDRESS, EMAIL_FROM);
var toAddress = new MailAddress(recipientEmail, "MY CLIENT NAME");
var smtp = new SmtpClient {
Host = EMAIL_HOST,
Port = EMAIL_PORT,
EnableSsl = EMAIL_SSL,
DeliveryMethod = EMAIL_DELIVERY_METHOD,
UseDefaultCredentials = EMAIL_DEFAULT_CREDENTIALS,
Credentials = new NetworkCredential(fromAddress.Address, EMAIL_PASS,EMAIL_HOST)
};
using (var message = new MailMessage(fromAddress, toAddress) {
Subject = subject,
Body = body,
Priority = MailPriority.High
}) {
smtp.Send(message);
}
}
I have enabled Less Secure Sign-in, and the configuration seems to be fine. What is the problem?
Try to remove the UseDefaultCredentials property.
If that doesn't work, set the properties individually (not using the object initialiser) and make sure Credentials is set after UseDefaultCredentials
see c# SmtpClient class not able to send email using gmail
I know this answere is a bit late, but You are using a NOT SECURE WAY to login to your gmail. Gmail actually throws an error but this is not send to you. You may receive an email that says something like:
Someone tried to connect to you gmail account from an unsecure
application
Or some similar. In this case you have to visit
https://www.google.com/settings/security/lesssecureapps
(Provided you are logged in)
and set this option to allow unsecure apps. Than you are allowed to send mails (even in this unsecure way).
Having the same problem atm but I dont want to allow unsecure apps, I want to change my code to be secure. But cant find anything that solves this.
Your code looks fine. Did you check that the email address hasn't been locked out? I.e. actually login to that email account on your browser. It happened to me before where the gmail account I was using got locked.
Guys I have a class where I am sending mail to all the students in database.When I send mails on my local host mails get send easily but when I upload my code to the server. I am getting this exception :
System.Net.Mail.SmtpException: The SMTP server requires a secure
connection or the client was not authenticated. The server response
was: 5.5.1 Authentication Required. Learn more at at
System.Net.Mail.MailCommand.CheckResponse(SmtpStatusCode statusCode,
String response) at System.Net.Mail.MailCommand.Send(SmtpConnection
conn, Byte[] command, MailAddress from, Boolean allowUnicode) at
System.Net.Mail.SmtpTransport.SendMail(MailAddress sender,
MailAddressCollection recipients, String deliveryNotify, Boolean
allowUnicode, SmtpFailedRecipientException& exception) at
System.Net.Mail.SmtpClient.Send(MailMessage message) at
HotelWeb.SMTPHelper.SendEmail(String From, String FromDisplayName,
String To, String Cc, String Bcc, String Subject, String Body, Boolean
SendMailInBackGround) in
e:\hostingspaces\ubi9009\ihmsgr.taqwatechnologies.net\wwwroot\App_Code\SMTPHelper.cs:line
140 at HotelWeb.MAILnSMS.sendBulkMail() in e:\
hostingspaces\ubi9009\ihmsgr.taqwatechnologies.net\wwwroot\App_Code\MAILnSMS.cs:line 95
My code works fine on local machine but doestnt work on server is like this :
public static void sendBulkMail()
{
_ds = new DataSet();
SMTPBAL smtpbl = new SMTPBAL(0);
smtpbl.LoadAll(_ds);
string server = _ds.Tables[smtpbl.SqlEntityX].Rows[0]["SMTPX"].ToString();
int smtpPort = WebHelper.Cast(_ds.Tables[smtpbl.SqlEntityX].Rows[0]["smtpPort"].ToString(), 0);
string From = _ds.Tables[smtpbl.SqlEntityX].Rows[0]["Email"].ToString();
string User = _ds.Tables[smtpbl.SqlEntityX].Rows[0]["User"].ToString();
string Password = _ds.Tables[smtpbl.SqlEntityX].Rows[0]["Password"].ToString();
string sDisclaimer = _ds.Tables[smtpbl.SqlEntityX].Rows[0]["Disclaimer"].ToString();
bool EnableSSl = WebHelper.Cast(_ds.Tables[smtpbl.SqlEntityX].Rows[0]["EnableSll"], false);
string EmailAddress = string.Empty;
StudentBAL _stbl = new StudentBAL(0);
_stbl.LoadAll(_ds);
foreach (DataRow dr in _ds.Tables[_stbl.SqlEntityX].Rows)
{
try
{
if (dr["Email"] != DBNull.Value)
{
if (IsValidMailAddress(dr["Email"].ToString()))
{
string Message = "Dear parent,<br/><br/> <br/> The Attendance for current course/semester of your ward," + dr["Name"].ToString() + " is available on the given below link.Please check and contact HOD in case any enquiry.<br/><br/><br/>Copy below link to your browsers address bar. <br/><br/>http://ihmsgr.taqwatechnologies.net/login/login.aspx <br/>User Name :" + dr["LoginEmailAddress"].ToString() + " / " + dr["EmailAddress"].ToString() + "<br/>Password : " + dr["Password"].ToString() + "<br/><br/><br/>Regard's<br/><br/>Institute of hotel management.<br/>Srinagar.";
SMTPHelper SMTP1 = new SMTPHelper(server, smtpPort, From, Password, EnableSSl, true);
SMTP1.IsHTML = true;
SMTP1.SendEmail(From, "Institute of hotel management", dr["Email"].ToString(), "", "", "Attendance status of your ward.", Message, false);
}
}
}
catch (Exception err) {
}
}
}
I am using hosting space on Server http://www.arvixe.com/ PLEASE HELP
That error message is typically caused by one of the following:
Incorrect connection settings, such as the wrong port specified for
the secured or non-secured connection
Incorrect credentials. Please verify the username and password
combination, to make sure the credentials are correct.
Also, if it still does not work, then try setting DeliveryMethod of SmtpClient as SmtpDeliveryMethod.Network
Following is the code snippet for the same
var smtp = new SmtpClient
{
Host = "smtp.gmail.com",
Port = 587,
EnableSsl = true,
DeliveryMethod = SmtpDeliveryMethod.Network,
UseDefaultCredentials = false,
Credentials = new NetworkCredential(fromAddress.Address, fromPassword)
};
You should use smtp account associated with your website domain to send email from website. Make sure that you use correct server and credentials as described at http://blog.arvixe.com/how-do-i-authenticate-emails-in-asp-net-using-smtp/ Also there is a support forum at http://forum.arvixe.com/smf/community-applications/asp-net-smtp-demo/ where you could ask for further help regarding your host.
I had a similar problem. There is a section which defines credentials. Use windows NTid and not email address
Credentials = new NetworkCredential("username", "pwd"), // email id would be username#domain.com
Goto your Google account setting then security section and search for "Less secure app access". Turn on this option and it should work.