How do email valdiation services verify and cleanse email addresses?

      How do email valdiation services verify and cleanse email addresses?

      hii,
      I have to clean up a large email list and I recently discover that some online platforms can do this for me.Before i start using such platforms and spend some money on those, i need to know what technology is behind those platforms and how its actually works.Let's take fo\zerobounce email validation system. What technology do they use to know which emails are valids and which are not?Try NeverBounce. They seem to know what they are experts in. I have never tried them,so try at your own risk.

      Thanks!

      I didn't find the right solution from the Internet.

      References: https://forums.digitalpoint.com/threads/how-do-email-valdiation-services-verify-and-cleanse-email-addresses.2815943/


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