Just curious, but don't e-mail clients ask you whether you want to send the acknowledgement or not? I know Thunderbird asks.
Ron W6RZ
On 3/29/19 00:31, Brian Kantor wrote:
Oh, I see.
The mail you are trying to deliver to me has a "Disposition Notification To" header line in it. This is a common trick used by spammers to prospect for valid mailboxes, because its purpose is to send the message sender an acknowledgement as soon as the message is opened by the recipient, whether the recipient wants to tell you that they've looked at your message or not.
I don't allow mail wanting those acknowledgement messages because I believe they are a privacy violation, so yours is getting rejected.
Delete that line from your email header and you'll get through just fine.
- Brian