What is an email validation script?

Question

Email Marketing

"first checks each new address, then after sending the email listens to the response and crosses out those who do not accept letters, even if the server said that the address exists"
What is the script for such an email address check? Is there a ready solution somewhere? Or explain, please, the logic of his work.

Answer 1

there is no 100% reliable way to check for a sucker, although in frimyla
it is simple, but not in all, such as rambler