send an email using SMTP without password in C# - c#

I have a web application using ASP.net and C#,in one step it will need
from the user to
send an email to someone with an attachments.
my problem is when the user will send the email i don't want to put their
password every time the user send.
i want to send an email without the password of the sender.
any way to do that using SMTP ?
and this is a sample of my code "not all".
the code is worked correctly when i put my password , but without it ,it
is not work, i need a way to send emails without put the password but
in the same time using smtp protocol.
private void button1_Click(object sender, EventArgs e)
{
string smtpAddress = "smtp.office365.com";
int portNumber = 587;
bool enableSSL = true;
string emailFrom = "my email";
string password = "******";
string emailTo = "receiver mail";
string subject = "Hello";
string body = "Hello, I'm just writing this to say Hi!";
using (MailMessage mail = new MailMessage())
{
mail.From = new MailAddress(emailFrom);
mail.To.Add(emailTo);
mail.Subject = subject;
mail.Body = body;
mail.IsBodyHtml = true;
// Can set to false, if you are sending pure text.
// mail.Attachments.Add(new Attachment("C:\\SomeFile.txt"));
// mail.Attachments.Add(new Attachment("C:\\SomeZip.zip"));
using (SmtpClient smtp = new SmtpClient(smtpAddress,portNumber))
{
smtp.UseDefaultCredentials = true;
smtp.Credentials = new NetworkCredential(emailFrom, password);
smtp.EnableSsl = enableSSL;
smtp.Send(mail);
}
MessageBox.Show("message sent");
}
}

I believe this can be accomplished easily, but with some restrictions.
Have a look at the MSDN article on configuring SMTP in your config file.
If your SMTP server allows it, your email object's from address may not need to be the same as the credentials used to connect to the SMTP server.
So, set the from address of your email object as you already are:
mail.From = new MailAddress(emailFrom);
But, configure your smtp connection one of two ways:
Set your app to run under an account that has permission to access the SMTP server
Include credentials for the SMTP server in your config, like this.
Then, just do something like this:
using (SmtpClient smtp = new SmtpClient())
{
smtp.Send(mail);
}
Let the configuration file handle setting up SMTP for you. This is also great because you don't need to change any of your code if you switch servers.
Just remember to be careful with any sensitive settings in your config file! (AKA, don't check them into a public github repo)

Related

How to send email from a C# program

I would like to add email functionality to a WinForm program I'm writing in C#. I have an Android app that has email functionality. What it does is set up the email but then lets the user choose the email program, etc. Once that is chosen the email body is completed. But it's up to the use to select what email app they want to use.
I would like to do the same in Windows but I don't see how. I have tried the following (based on other questions and responses here) :
_from = new MailAddress("my email address", "xxxx");
_to = new MailAddress("xxxx3333#gmail.com", "yyyy");
SmtpClient smtp = new SmtpClient("smtp.gmail.com");
smtp.UseDefaultCredentials = true;
smtp.Port = 587;
smtp.EnableSsl = true;
smtp.DeliveryMethod = SmtpDeliveryMethod.Network;
smtp msgMail = new MailMessage();
smtp.Body = text;
msgMail.Subject = "Subject";
msgMail.From = _from;
msgMail.To.Add(_to);
smtp.EnableSsl = true;
msgMail.Subject = _subject;
msgMail.Body = Text;
msgMail.IsBodyHtml = false;
try
{
mailClient.Send(msgMail);
}
catch (Exception ex)
{
string msg = "Exception caught in sending the email: " + ex.ToString();
showMessage(msg);
}
msgMail.Dispose();
But I get:
The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required.
With similar code in Android, my program just gets to an email form but lets the user decide what email add they will use.
Is there a way to do this in Windows?
There is an almost identical question and response here:
C# Windows Form Application - Send email using gmail smtp
And I think I've followed this but...doesn't work.
To directly answer your question - you probably haven't enabled less secure apps on the gmail account you are using.
Otherwise though, you could investigate the syntax of mailto if you want to let the user elect a mail client to use to send the email: https://www.labnol.org/internet/email/learn-mailto-syntax/6748/
From the link:
Send an email to Barack Obama with the subject “Congrats Obama” and some text in the body of the email message
<a href=”mailto:obama#whitehouse.gov?
subject=Congrats%20Obama&body=Enjoy%20your%20stay%0ARegards%20″>
This isn't directly related to C#/Windows - but I do know entering mailto:someone#somewhere.com at the Run prompt works:
Presumably then you could do something like: (untested)
Process.Run("mailto:someone#somewhere.com");
From the server response messages it looks like you have to provide login credentials before you are allowed to send.
Replace:
smtp.UseDefaultCredentials = true;
With:
smtp.Credentials = new System.Net.NetworkCredential("yourusername", "yourpassword");
This should do the trick.
You may have forgotten in your code to add the Host
Try to use this :
SmtpClient smtp = new SmtpClient();
smtp.UseDefaultCredentials = true;
smtp.Host = "SRVMAIL";

Sending mail through C# with gmail is not working after deploying to host

I am trying to send mail through Gmail. I am sending mail successfully when I am testing on localhost, but this does not work when I upload it to a web host. I am seeing this type of error:
Request for the permission of type System.Net.Mail.SmtpPermission, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089 failed.
Whenever I am using port 25 get this type of error below:
The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required
Below is my code of send email.
MailMessage mail = new MailMessage("host#gmail.com","User#gamil.com");
SmtpClient SmtpServer = new SmtpClient("smtp.gmail.com");
mail.Subject = "Any String"
mail.Body = mailbody;
mail.IsBodyHtml = true;
SmtpServer.Port = 587;
SmtpServer.DeliveryMethod = SmtpDeliveryMethod.Network;
SmtpServer.UseDefaultCredentials = false;
SmtpServer.Credentials = new System.Net.NetworkCredential("xyz#gmail.com","123");
SmtpServer.EnableSsl = true;
SmtpServer.Send(mail);
Is there any solution? Please suggest to me!
Edit: OP Added extra information crucial to answering this question, but I'm keeping the old answer around as it might still help someone
New Answer:
This StackOverflow question already answered this question
OldAnswer:
As this StackOverflow answer already answered, you changed the Port on the SMTP Server to 587 instead of its default (25) and this requires elevated permissions causing this error change this:
SmtpServer.Port = 587;
to this:
SmtpServer.Port = 25;
and it should work
Note: When using SSL the port needs to be 443
Answer : Your code add SmtpDeliveryFormat.SevenBit
Example:
using (SmtpClient smtp = new SmtpClient())
{
NetworkCredential credential = new NetworkCredential
{
UserName = WebConfigurationManager.AppSettings["UserName"],
Password = WebConfigurationManager.AppSettings["Password"],
};
smtp.Credentials = credential;
smtp.DeliveryMethod = System.Net.Mail.SmtpDeliveryMethod.Network;
smtp.DeliveryFormat = SmtpDeliveryFormat.SevenBit;
smtp.Host = WebConfigurationManager.AppSettings["Host"];
smtp.Port = WebConfigurationManager.AppSettings["Port"].ToNcInt();
smtp.EnableSsl = Convert.ToBoolean(WebConfigurationManager.AppSettings["EnableSsl"]);
smtp.Send(mail);
}
Try This
using System;
using System.Net;
using System.Net.Mail;
namespace AmazonSESSample
{
class Program
{
static void Main(string[] args)
{
// Replace sender#example.com with your "From" address.
// This address must be verified with Amazon SES.
String FROM = "a#a.com";
String FROMNAME = "ABC";
// Replace recipient#example.com with a "To" address. If your account
// is still in the sandbox, this address must be verified.
String TO = "a#a.com";
// Replace smtp_username with your Amazon SES SMTP user name.
String SMTP_USERNAME = "a#a.com";
// Replace smtp_password with your Amazon SES SMTP user name.
String SMTP_PASSWORD = "ASJKAJSN";
// (Optional) the name of a configuration set to use for this message.
// If you comment out this line, you also need to remove or comment out
// the "X-SES-CONFIGURATION-SET" header below.
String CONFIGSET = "ConfigSet";
// If you're using Amazon SES in a region other than US West (Oregon),
// replace email-smtp.us-west-2.amazonaws.com with the Amazon SES SMTP
// endpoint in the appropriate AWS Region.
String HOST = "smtp-relay.sendinblue.com";
// The port you will connect to on the Amazon SES SMTP endpoint. We
// are choosing port 587 because we will use STARTTLS to encrypt
// the connection.
int PORT = 587;
// The subject line of the email
String SUBJECT =
"Amazon SES test (SMTP interface accessed using C#)";
// The body of the email
String BODY =
"<h1>Amazon SES Test</h1>" +
"<p>This email was sent through the " +
"<a href='https://aws.amazon.com/ses'>Amazon SES</a> SMTP interface " +
"using the .NET System.Net.Mail library.</p>";
// Create and build a new MailMessage object
MailMessage message = new MailMessage();
message.IsBodyHtml = true;
message.From = new MailAddress(FROM, FROMNAME);
message.To.Add(new MailAddress(TO));
message.Subject = SUBJECT;
message.Body = BODY;
// Comment or delete the next line if you are not using a configuration set
message.Headers.Add("X-SES-CONFIGURATION-SET", CONFIGSET);
using (var client = new System.Net.Mail.SmtpClient(HOST, PORT))
{
// Pass SMTP credentials
client.Credentials =
new NetworkCredential(SMTP_USERNAME, SMTP_PASSWORD);
// Enable SSL encryption
client.EnableSsl = true;
// Try to send the message. Show status in console.
try
{
Console.WriteLine("Attempting to send email...");
client.Send(message);
Console.WriteLine("Email sent!");
}
catch (Exception ex)
{
Console.WriteLine("The email was not sent.");
Console.WriteLine("Error message: " + ex.Message);
}
}
}
}
}

Failed to send an EMail with body contains ip address and port no

I have create function to send an email. This function was work successful on localhost but on server its failed without any exception. I know the problem comes from my Port on IP Address.
The sample body is string body = "<p>Please click here</p>Thank You."
The problem is : between IP Address and Port.
Successful send an email if i remove :.
Do you guys have any ideas?
public void Sent(string sender, string receiver, string subject, string body)
{
using (MailMessage mail = new MailMessage(sender, receiver))
{
using (SmtpClient client = new SmtpClient())
{
client.Port = 25;
client.DeliveryMethod = SmtpDeliveryMethod.Network;
client.UseDefaultCredentials = false;
client.Host = "mail.companyName.com.my";
mail.Subject = subject;
mail.IsBodyHtml = true;
mail.Body = body;
client.Send(mail);
}
}
}
You are doing it right, the code to send the mail is ok (you may want to revise the function name and make the smtp host name configurable, but that is not the point here).
The e-mail delivery fails on a relay, there is no immedieate feedback (no exception) to the client about this kind of failure.
The best bet is the IncreaseScoreWithRedirectToOtherPort property set in Set-HostedContentFilterPolicy in case your mail provider is Office365, or a similar spam filter mechanism in any other mail provider that is encountered down the mail delivery chain.
You can set a reply-to address and hope that the destination server will bounce a delivery failure that gives you more information. Or have the admin of the mail server look up the logs. More information here:
https://serverfault.com/questions/659861/office-365-exchange-online-any-way-to-block-false-url-spam
Try setting the 'mail.Body' to receive a Raw Html message instead of a encoded string, like:
mail.Body = new System.Web.Mvc.HtmlHelper(new System.Web.Mvc.ViewContext(), new System.Web.Mvc.ViewPage()).Raw(body).ToString();
Or put a using System.Web.Mvc at the beginning so it gets shorter and easier to understand:
using System.Web.Mvc
mail.Body = new HtmlHelper(new ViewContext(), new ViewPage()).Raw(body).ToString();

How do I send an email with Gmail and SmtpClient when the sending account uses two factor authentication?

SmtpClient smtpClient = new SmtpClient();
NetworkCredential basicCredential =
new NetworkCredential("sender#gmail.com", "password");
MailMessage message = new MailMessage();
MailAddress fromAddress = new MailAddress("sender#gmail.com");
smtpClient.EnableSsl = true;
smtpClient.Host = "smtp.gmail.com";
smtpClient.Port = 587;
smtpClient.UseDefaultCredentials = false;
smtpClient.Credentials = basicCredential;
message.From = fromAddress;
message.Subject = "your subject";
//Set IsBodyHtml to true means you can send HTML email.
message.IsBodyHtml = true;
message.Body = "<h1>Hello, this is a demo ... ..</h1>";
message.To.Add("receiver#gmail.com");
try
{
smtpClient.Send(message);
}
catch (Exception ex)
{
//Error, could not send the message
ex.ToString();
}
// The thing is that this code works fine for gmails without phone number protection. Exception occurs when using this code with gmails that are protected(verified) via the client phone number.
One of the solution is to use a remote server to access clients mails.
Now my question is there another method to solve this issue ? other than third parties.
If I understand you correctly, you're saying the Google account is using two-factor authentication.
If that's the case, you need to create an Application Password for this. Go to https://security.google.com/settings/security/apppasswords once logged in as the account you want to two-factor auth with.
In the list, under Select App choose "Other" and give it some name. Click Generate, and write this password DOWN cause you will only ever see it ONCE. You will use this in your authentication. It will be 16-characters long and the spaces don't matter, you can include them or omit them. I included them here just because.
NetworkCredential basicCredential =
new NetworkCredential("sender#gmail.com", "cadf afal rqcf cafo");
MailMessage message = new MailMessage();

How to set From Address to any email other gmail in ( Sending Email in .NET Through Gmail )?

In this post Sending Email in .NET Through Gmail we have a code to send email through gmail, in the send mail we find from Field contain gmail account that I used
I use the same code but by changing the From Address to any email I want ans set gmail address in Credentials as bellow
var fromAddress = new MailAddress("AnyEmai#mailserver.com", "From Name");
var toAddress = new MailAddress("to#example.com", "To Name");
const string fromPassword = "fromPassword";
const string subject = "Subject";
const string body = "Body";
var smtp = new SmtpClient
{
Host = "smtp.gmail.com",
Port = 587,
EnableSsl = true,
DeliveryMethod = SmtpDeliveryMethod.Network,
UseDefaultCredentials = false,
Credentials = new NetworkCredential("from#gmail.com", fromPassword)
};
using (var message = new MailMessage(fromAddress, toAddress)
{
Subject = subject,
Body = body
})
{
smtp.Send(message);
}
But in the sent email gmail account still appear in From Address and AnyEmai#mailserver.com not appear ... is there any way to do that ?
It's that way by design. You have to find another way to send outbound emails so that the return address you want shows up (I've been there, there seems to be no way to spoof the from address).
Shall you check this question change sender address when sending mail through gmail in c#
I think it is related to your inquiry.
You can import an email id in your gmail account using Mail Settings >> Accounts and Import options and that can be used for sending the mails, however if you are want to use some random email id everytime to send the mails it is not possible. Gmail will treat that as a spoofing/spam and it will reset the mail address to your original mail id before sending the mail.
using System.Net;
using System.Net.Mail;
public void email_send()
{
MailMessage mail = new MailMessage();
SmtpClient SmtpServer = new SmtpClient("smtp.gmail.com");
mail.From = new MailAddress("from#gmail.com");
mail.To.Add("to#gmail.com");
mail.Subject = "Your Subject";
mail.Body = "Body Content goes here";
System.Net.Mail.Attachment attachment;
attachment = new System.Net.Mail.Attachment("c:/file.txt");
mail.Attachments.Add(attachment);
SmtpServer.Port = 587;
SmtpServer.Credentials = new System.Net.NetworkCredential("from#gmail.com", "mailpassword");
SmtpServer.EnableSsl = true;
SmtpServer.Send(mail);
}
There are many other mail services from which you can achieve the same but not through the gmail. Checkout the blog Send email in .NET through Gmail for sending mail using different properties.
The email address needed to be verified by gmail from the account settings.
Please find my blog post for the same describing it in detail, the steps to be followed:
http://karmic-development.blogspot.in/2013/10/send-email-from-aspnet-using-gmail-as.html
before following all the above steps, you need to authenticate your gmail account to allow access to your application and also the devices. Please check all the steps for account authentication at the following link:
http://karmic-development.blogspot.in/2013/11/allow-account-access-while-sending.html

Categories

Resources