What is invalid, harvested and blacklisted email addresses?

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1. What is invalid email addresses?

Invalid email is those emails which are not formatted as per internet email format standards.


  • More than one ‘@’ sign
  • Username is longer than 300 characters
  • You’re entering ‘@gmail’ or ‘@yahoo’ instead of ‘@gmail.com’ or ‘@yahoo.com’
  • Extra space somewhere in the email address
  • Addresses that include certain special characters

2. What is harvested email addresses?

Harvested records are the records which are filtered because of many reasons.

–  We check different patterns in the email like:
*spam*, *privacy*, *asdf*, ^webmaster*, ^postmaster, etc

– We check Blacklisted TLDs (Top Level Domains):



– We check Blacklisted SLDS (Second Level Domains):

Example:  someone@maharera.gov.in

– We check Blacklisted SLDS long:
*.co.jp, *.nic.in, etc


– We check super blacklisted domains like:
spamhaus.org, spamcop.net, sorbs.net, etc


– Blacklisted sender names:
sysadmin@, whois@, listmanager@, maildaemon@, root@, etc


3. What is blacklisted email addresses?

A blacklisted email is an email that is excluded from receiving your campaigns due to certain reasons. None of your campaigns will be sent to these emails after they have been blacklisted. However, these emails will still be in your lists and in your database. An email can be blacklisted due to several reasons:

  • We have lots of blacklisted domains and email address which we have collected from our mailing activities over the years.
  • They have resulted as a hardbounce (ex: their email address does not exist)
  • They have marked your emails as SPAM
  • They have unsubscribed from your emails
  • or you have blacklisted them manually


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