Gmail Error :The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required

Question

I am using following code to send email. The Code works correctly in my local Machine. But on Production server i am getting the error message

var fromAddres         


        

Answer 1

I tried all of the suggestions found here, from enabling less secure apps, to trying port 587... nothing worked. Finally I just commented out the line UseDefaultCredentials = false. Everything worked if I didn't touch that boolean.