cfml

ACLs have been deprecated for S3 buckets for quite some time. AWS really does not want you using these. That's why they are disabled by default when you create a bucket. They continue to be allowed only because AWS _rarely_ removes features. The preferred method is to use IAM permissions to allow access to objects or buckets.

It's quite possible that the IAM user or role you are using to access the bucket does not have permission to do so. I suggest verifying the IAM user permissions and reconsidering whether or not an ACL is needed versus individual, per-user signed requests for retrieving or putting objects.