First, I understand that my post may be similar to some other posts here. As in the following (possibly duplicate) post: Why do users reply to messages clearly marked as do not reply
Reading that post was hard because the responders kept going off topic. It's a few years old and no real solution was discovered.
A user, uses a contact form on the website and sends a message to the website owner, (my customer).
The contact form posts the email contents to an external server which composes an email and sends it to the owner's email address.
(The owner's website is not on the same server that sends the emails. The server can send, but doesn't accept emails.)
The owner receives the user's message in their own email app (not on their website), and they want to respond to the user.
The owner clicks the reply button on their email app, writes their response and clicks send, expecting the user will receive that message.
Finally, the user never receives the owner's response.
End of Scenario.
When the owner clicks the 'Reply' button on their email app, they're replying to the sender of the email. In this case, the sender is the mail server host that was used to send the message to the owner and not the user.
I'm probably the only one experiencing this with my customers!?!
Asking the owner not to use the reply button, doesn't mean anything. They're human and sometimes forget, and use it any way.
This isn't a case about whether to use a mailto link inside the email body vs something else. That's a whole other issue. The email received by the owner would have some means of contacting the user in the message body, even if they don't use it.
This is about, trying to provide a better user experience for the owner, even when they forget and use the reply button on their email app.
The easiest way I can think of, would be to set the reply-to header on the email to the user's email address when composing the email to the owner at the server. But I think that's not allowed in 'can spam' rules. I also fear that when the user receives the owner's response in that manner, it would end up in the user's junk mail folder.
What would be a safe and reliable way to achieve this user experience? Is this even possible? How do others handle this?