What is the meaning of 40 GENERAL BOUNCE in a bounced email?

Question

Is it considered a soft bounce, like a transmission or SMTP error, and we should try again? Or treat it as a hard bounce?

Thanks.

Answer 1

According to the RFC, that means that a transient failure occurred, and that trying again later may succeed. However, there's no more specific information available.

Unfortunately, not all ISPs implement the standards correctly, so you may want to check with the particular ISP that's bouncing the email.

More information: http://www.faqs.org/rfcs/rfc1893.html