Spam notifications are the messages received by the Email gateway protection system or Email server when your email has been temporarily blocked by them. This happens due to many reasons such as your sending domain / IP has been blacklisted globally, Domain/IP is new has not maintained well-sending reputation, your email body contains (suspicious link, bad keyword) or you are sending email against receipt corporate policy.
Spam complaint is triggered by receipt end, the mailbox providers such as Yahoo, Gmail, Hotmail provide the option such as a button to their user to report any spam to their spam protection system. There can be many reasons when a user clicks on the spam button such as didn’t opt-in for your email, they find some suspicious content, you keep bothering and don’t honor their unsubscribe request. Every mailbox provider has own algorithm to treat spam reports, more spam complaints can lead to serious damage your sending domain and our email server IP address.