I encountered the error when trying to refactoring old code against a new S3 bucket. New S3 buckets no longer support V3, and thus require the new V4 signature.
In order to make the code work, please uninstall the previous AWS SDK, e.g. “ASWSDK 2.3.3”.
Then install the Nuget Packages AWSSDK.Core and AWSSDK.S3 and AWSSDK.SQS, after which you can rebuild and run your code successfully.
You also need to change some code such as Amazon.AWSClientFactory.CreateAmazonS3Client() is replaced by a new AmazonS3Client().