Amazon SES for Emails
As an Admin, go to Settings -> Billic Settings.You will see a setting for "Amazon SES For Emails".
It should be in the format of: email.eu-west-1.amazonaws.com wJt6HNVwJt6HNV S2b78MphS2b78MphS2b78MphS2b78MphS2b78Mph
Where...
email.eu-west-1.amazonaws.com DOES NOT contain "smtp" in the domain name. It should only be "email".
email.eu-west-1.amazonaws.com is the correct location of your Amazon SES service.
wJt6HNVwJt6HNV is your Access Key ID (If you create an SMTP account this is the generated username)
S2b78MphS2b78MphS2b78MphS2b78MphS2b78Mph is your Access Key Secret (If you create an SMTP account this is the generated password)
If you get a permission denied error when trying to send email (seems to always happen at time of writing) you may need to go into Amazon IAM and edit the policy for the user you created for SMTP. Change "SendRawEmail" to "SendEmail".