Gmail: 530 5.5.1 Authentication Required. Find out more at

Question

This Go program successfully sends email from my home computer, but the following error appears on the DigitalOcean virtual server:

panic: 530 5.5.1 Authentication Required. Learn more at 

Here is the code:

 auth := smtp.PlainAuth("", "[e-mail]", "PASSWORD", "smtp.gmail.com") msg := "Subject: Hello\r\n\r\nWorld!" e = smtp.SendMail("smtp.gmail.com:587", auth, "[e-mail]", []string{email}, []byte(msg)) if e != nil { panic(e) } 

Answer 1

Get the security settings for your Gmail account and set the permissions for the Less Secure Apps to Enabled . Worked for me.

Answer 2

Derp! I signed up for this account and the warning message “Suspicious login” appeared at the top of the page. After clicking on the warning and authorizing access, everything works.

Answer 3

You need to go here https://security.google.com/settings/security/apppasswords

then select Gmail and then select the device. then click "Create." Just copy and paste the password that Google creates.

Answer 4

You need to enable POP and IMAP mail in the email settings that you use to send mail. Good luck