ERPNext Amazon S3 Backup settings

Thanks for your reply…
it worked after I change the AWS User permission policy…
earlier I was using a custom policy…

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "s3:ListAllMyBuckets",
                "s3:PutObject",
                "s3:GetObject"
            ],
            "Resource": [
                "arn:aws:s3:::*"
            ]
        }
    ]
}

changed it to amazon standard permission of AmazonS3FullAccess

its having following permission…

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": "s3:*",
            "Resource": "*"
        }
    ]
}