How to sent mail using smtp config.?

Raja

9y1.5k.NET

I use below code to mail config .thats works in other applications but my application shows the below error how to fix it.

Msg.IsBodyHtml = true;

SmtpClient smtp = new SmtpClient();
smtp.Host = ConfigurationManager.AppSettings["MailServer"];
System.Net.NetworkCredential NetworkCred = new System.Net.NetworkCredential();
Msg.From = new MailAddress(ConfigurationManager.AppSettings["MailFrom"]);
NetworkCred.Password = ConfigurationManager.AppSettings["MailPassword"];
smtp.Credentials = NetworkCred;
smtp.Port = 25;
smtp.EnableSsl = true;

ServicePointManager.ServerCertificateValidationCallback = delegate(object s, System.Security.Cryptography.X509Certificates.X509Certificate certificate, X509Chain chain, SslPolicyErrors sslPolicyErrors)
{
return true;
};

smtp.Send(Msg);

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

6 Replies

Know the answer? Post it — somebody with the same question will find it here.

Amit Gupta9y ago
Accepted answer
Hey
The solution is under the below points
1. Verify that username and password are correct

2. Turn on less secure app in gmail settings

3. If 1 and 2 doesnot resolve the problem then there might be geographic location problem. Basically gmail doesnot allow you to access from remote location if it was using through any app. If it was accessing from other location, gmail (for security reason) ask you that your email account is accessing from remote location, just allow this( that it was you) in your gmail to allow signin from your app.

4. Try opening gmail from browser at remote location (where your application is running) and then signout.

5. Try changing port no from 25 to 587.

6. All done

Good luck !
+3
Raja9y ago
Hi,

Amit Gupta
i have enable the settings which i use for sent mail.but still the same error is occurs
+1
Amit Gupta9y ago
The setting must be enable to those mail id from which you are sending the mail i.e MailFrom.
+2
Raja9y ago
and one more clarification i enable this settings to which mail id to use sending the mail?
+1
Raja9y ago
Amit Gupta
yes i use gmail smtp server.
if i on the settings mail is working?
+1
Amit Gupta9y ago
Hey
Are you sending this mail with gmail smtp server?

You need to allow less secure app to true at below link
https://myaccount.google.com/security
+3

How to sent mail using smtp config.?

Amit Gupta

Amit Gupta