Using third-party automated applications like SyncBackPro with Amazon S3 requires the use of special credentials called Access Key & Secret Key, which need to be obtained from Amazon direct (once you have an S3 account). You can currently access these via

After logging in, on the Access Keys tab, you'll find to the right of your active Access Key a link labeled "Show"...which when clicked will reveal your Secret key to you.

Note that direct cloud service functionality is a SyncBackPro-only feature.