What Is Email verification process?

Email Address Syntax Check: This removes improperly formatted email addresses, according to IETF standards.
Domain/MX Records Check: This verifies the DNS entries of an email address. If a domain is found to be invalid, or an MX entry is missing, this process marks the corresponding email address as invalid.
Role-Based Account Detection: Email sends to role-based such as postmaster@, info@, sales@, admin@, etc. can negatively impact your deliverability, and even blacklist you with some ISPs. This process detects and flags such addresses.
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Transcript

2. What Is The Process Of Validating An Email Address? The validity of an email address can be measured through a combination of several validation techniques and internal databases checks with some proprietary algorithms. At the end of list validation process, invalid email addresses will be filtered out and the outcome will be a clean email list – validated and ready for marketing and business requirements.
3. Email address syntax check This process will remove any improperly formatted email addresses. The email addresses are validated according to the IETF standards.
4. Domain/MX records check This process will check the DNS entries of an email address. When the domain is invalid or MX entry is missing, process will mark this email address as invalid.
5. Role based Account detection Role based account email addresses such as postmaster@, info@, support@, admin@, etc. will be detected and flagged appropriately.
6. Disposable email address detection Throwaway / disposable email addresses or junk collector email addresses will be detected and processed appropriately. These email addresses are used for a one-time use to sign up or to bypass login form with providing a valid email address.
7. HoneyPot/Spam trap detection This process will detect spam seeds, BOTs, honeypots, black list or bogus emails addresses. In this process, all the emails are checked against the known list of email address / domains used for trapping spammers.
8. Checking DNSBLs and URI DNSBLs for blacklisting A DNS-based Blackhole List (DNSBL) or Real-time Blackhole List (RBL) is a list of IP addresses which are most often used to spamming. A URI DNSBL is a DNSBL that lists the domain names which are found in the body of spam email messages, but generally not found inside legitimate messages. In this process, email address or IP address is checked against the known DNSBLs and URI DNSBLs to trap spam networks.
9. Final Verification This phase performs deep level SMTP verification on each email address. Each email address will be verified for mailbox existence without sending actual emails on that address.
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