An anti-spam program that requires a human being on the sender’s end to respond to an emailed challenge message before their messages can be delivered to recipients. Senders who answer the challenge successfully are added to an authorization list. Bulk emailers can work with challenge-response if they designate an employee to watch the sending address’ mailbox and to reply to each challenge by hand.
The 3 Things To Avoid When Emailing Your List
When you decide to have an opt-in list, it is not just a matter of sending your subscribers your promotional newsletters or catalogs.
