Cannot list buckets by users other than root user

Question

Initially, I didn't know the best practice of not creating IAM user. As such I created access key for root user and created s3 buckets as root user and everything worked fine. Later on as suggested by best practices I created an IAM user and attached it with both policies: AdministratorAccess and AmazonS3FullAccess. However, I am unable to list the buckets as the newly created user (say admin). With root I have no problem listing buckets or doing any other action.
I ran the following command to list attached policies to the admin user
```
aws iam list-attached-user-policies --user-name admin --profile root
```
Output

```
{
    "AttachedPolicies": [
        {
            "PolicyName": "AdministratorAccess",
            "PolicyArn": "arn:aws:iam::aws:policy/AdministratorAccess"
        },
        {
            "PolicyName": "AmazonS3FullAccess",
            "PolicyArn": "arn:aws:iam::aws:policy/AmazonS3FullAccess"
        },
        {
            "PolicyName": "AWSLambda_FullAccess",
            "PolicyArn": "arn:aws:iam::aws:policy/AWSLambda_FullAccess"
        }
    ]
}

```

Answer

Hi Saurav,

When accessing objects in Amazon S3 there are two possible policies that can affect the outcome
1. IAM User/Role Access Policies. It seems your admin user has enough permissions from what you attach
2. [Amazon S3 Bucket Policies](https://docs.aws.amazon.com/AmazonS3/latest/userguide/example-bucket-policies.html). The bucket can allow or block permissions. If the IAM User has permissions to access the bucket, but the bucket policy has an explicit deny, then the overall action is to DENY that access.
In your case I would check the Amazon S3 Bucket policies in order to see if it has a policy blocking it's use.

Hope this helps!

Cannot list buckets by users other than root user

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