Create a .NET SDK connection by using the default credentials

using Amazon;
using Amazon.S3;
using Amazon.S3.Model;
using Amazon.S3.Util;

AmazonS3Config S3Config = new AmazonS3Config
{
  ServiceURL = "http://system.example.com"
};

string accessKeyId = "00000000000000";
string secretAccessKey = "000000000000000000000000000000";

AmazonS3Client client = new AmazonS3Client(accessKeyId , secretAccessKey ,S3Config);