The ‘BoxTrapper’ functions as a email spam filter for email accounts (addresses) in cPanel. The ‘BoxTrapper’ works through “challenge-response” verification. When an email is sent to an account that has enabled BoxTrapper, BoxTrapper automatically sends a verification email in response. This verification email requires the original sender to send a reply or click a link. After the sender does this, BoxTrapper delivers the original message to the intended recipient’s account. The goal in enabling BoxTrapper is to block email senders who do not reply to the verification email or click the verification link. Here is the steps for the question “How can I activate BoxTrapper on my cPanel server?“ Step I : login to the WHM control panel.