SMTP mail transfer error authentication

Question

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

 

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

 

Exception Details: 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

 

Source Error:

 

Line 53: }; Line 54: SMTP.EnableSsl = true; Line 55: SMTP.Send(PassRecMail); Line 56: Line 57: lblPassRec.Text = "Check your email to reset your password.";

 

Source File: e:\My Website\firstWebsite\ForgotPassword.aspx.cs Line: 55