What is a spam complaint?
A spam complaint is when one of your subscribers has reported receiving an unwanted email, otherwise known as ‘abuse’ of their email address.
Within most modern email clients there are very easy ways to mark an email as spam, usually a simple and obvious button. In other cases, recipients can forward an unsolicited email through a third party system or forward an email directly to the relevant abuse department. Lots of users don't even know what is happening behind the scenes.