Is there any idea about this mail error which I see when setting to Yahoo smtp?
Failed to send an email from the user with id '3500' to the user with id '10466' due to the following error: "SMTP Error: data not accepted.SMTP server error: DATA END command failed Detail: Error sending message for delivery. SMTP code: 554 Additional SMTP info: 6.6.0".
This is not always. Some times I see that. I don't see that for gmail.