In the past, when someone would reply to a private message notification email (or other system emails), it would get sent to the webmaster's email. The webmaster would have to forward the message to the intended person or would reply to the person letting them know that their message was not sent. I don't think we (webmasters) want to be reading someone's message that was intended to be private to determine the recipient to whom to forward the message.
I created an automatic responder email (do-not-reply @cbbqa.org) to handle this. So whenever someone replies to the system emails like the private message notifications, it will automatically reply with the following message:
**Please do not reply to this email. Replies are sent to an unmonitored mailbox.**
Dear *Sender Name* ,
You have replied to a system email. If you were trying to reply to a private message, please log in
to the forum and reply using the forum's messaging service
If you have any questions regarding this, please email webmaster @cbbqa.org