ActivePipe runs an email validation service on all new contacts to pre-empt potential hard bounces and protect your mailing reputation.

If a contact is unsubscribed by reason of Failed validation or Bad email, this means that the contact's email address was flagged as invalid or non existent during ActivePipe validation. 

You can double check an emails validity using a third party site such as:

• https://www.verifyemailaddress.org
• https://verify-email.org
• https://email-checker.net
• https://tools.verifyemailaddress.io
• https://neverbounce.com
• https://verifalia.com/validate-email

If you believe that any of your contacts have been failed in error, contact the ActivePipe support team (referencing the relevant email address/es) and our team will be happy to assist.

See other reasons a contact may be unsubscribed here