How the email address gets verified?

RS Email Verifier uses 4 Level of verification listed below which just works on the same algorithm as ISP mail systems works.

– Email Address Syntax: Email Verifier automatically checks for email syntax and remove them on import.
– Email Domain Availability: Email Verifier software check for email address domain availability and Domain name server (DNS) will be extracted. If particular domain is not available, then it will be marked as “bad”.
– SMTP Connection to MX server: Email Verifier then tries to establish SMTP connects to the highest priority Mail Server. Please make sure Port 25 is open.
– Simulate Message Verification: After successful connection, email verifier simulates the sending of a message, check mailbox existence and disconnect before sending message