Users didn't receive emails but it works well previously

hi, I used the ojs, the system used SMTP to send email, it works well for two years, but these days it can’t send emails or just users don’t receive them, I don’t know it belongs which one case. There is no any error logs about it in the server. I have looked up some questions in the forum, but no results. Can you give me some advice to find the error? Thank you very much.

hello @xiongfeiyan .

What SMTP server are you using?


Hi, I use this server
; SMTP server settings
smtp_server = “ssl://”
smtp_port = 465

Thank you, @juanito, I had solved it already, the smtp server changed the user login authentication method some days ago.