Any email that Amazon Simple Email Service (SES) records as a hard bounce will automatically be placed in their suppression list (somewhat like a blacklist) for 14 days. If you know that the email address is a good address, or if the address became an active email address after you sent your Soapbox Mailer email, you can do the following to remove the email address from the Amazon SES suppression list.
1) Fill out the Amazon SES suppression list removal form
2) Wait 14 days, after which time Amazon SES will try to deliver the email without hitting the suppression list
Happy emailing!