For the most up-to-date information regarding blacklisted emails, consult our Email Delivery FAQs: 
https://bb-email-services.docs.blackbaud.com/faqs/processing/#ProcessingBLRemoveall

To prevent your email from being blacklisted, your Blackbaud Application does not send email to an invalid account. For each email address in Invalid Accounts, you can view the bounce error that caused the ISP to report the account as invalid. If you feel an account is incorrectly marked invalid, you can mark it as active to include it in a future mailing (BB551816).

Additional information about blacklisting (BB346004).