Where can I get the list of invalid email or blacklisted email in my contact/guestlist?
You can export the list of invalid email or blacklisted email using Evenesis.
You can go to Database>>Guestlist>>Click on Other Action Button>>Select Export Invalid Emails from Other Action Dropdown Menu
The email is mark blacklisted by the system if there the email has a bounced record. If you’re sure that one of the emails that were blacklisted by the system is valid, to let our support team know in order for us to whitelist the email address.
Sometimes a valid email can be bounced because of various reason and one of the common reason is the inbox of the email is full.