Features > Anti-Spam > Challenge & Response Challenge & ResponseReject at SMTP with this message
 Reject at SMTP with this message will return a permanent SMTP failure code with the text that is given here. You can use the macros $header(field) to refer to header fields and $hamtoken to return a unique address that can be used to bypass the anti-spam system for seven days.
Default setting
Challenge & Response in action
If you configure Mailtraq to reject suspected spam at SMTP, Mailtraq will reply to the sender of a suspect message with an email containing the Default setting information above, which includes a link to a webpage that explains to the sender why their message has been rejected.
Nearly all rejections will be for true spam, and the rejected message will not be responded to. Occassionally, however, Mailtraq will suspect a real message to be spam, and the 'challenge & response' system will allow the sender of the rejected message to resend their email and be sure it will get through.
The webpage explains as follows:
Your message to was rejected
Our mail server rejected your message because it appeared to be spam. This page explains why, and how to resend your message without it being rejected again.
Please re-send your message to this temporary address: $hamtoken
This temporary address is valid for seven days, and allows your message to bypass our spam detection system.
The sender simply has to resend their original message to the temporary address provided.
The entry $hamtoken is replaced by a unique identifier each time.
The webpage is served at no charge from our web servers - or you can serve a similar page from your own website. | 
