C# AWSSDK从v2.3更新到v3.1后，文件上载代码不起作用

上个月，我们将Amazon AWSSDK nuget包从2.3版更新为3.1版。之后，没有任何文件被上传到服务器，但我没有得到任何错误。我们尝试访问我得到404或0字节文件的位置

这是密码。我错过了什么

            var keyName = Globals.configSettings.AmazonS3ApiKey;
            var apiId = Globals.configSettings.AmazonS3ApiId;
            var fileName = !string.IsNullOrEmpty(ChangedFileName) ? ChangedFileName : fileUploadDownloadable.FileName;

            using (var fileTransferUtility = new TransferUtility(new AmazonS3Client(apiId, keyName, Amazon.RegionEndpoint.USEast1)))
            {
                var bucketName = Globals.configSettings.AmazonS3ApiBucketName;
                var request = new TransferUtilityUploadRequest
                {
                    BucketName = bucketName,
                    Key = "images/downloads/" + fileName,
                    InputStream = fileUploadDownloadable.PostedFile.InputStream
                };

                fileTransferUtility.Upload(request);
            }

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谢谢你的帮助

由于某种原因，当我将代码更改为此时，它开始工作。。我不知道为什么

            var keyName = Globals.configSettings.AmazonS3ApiKey;
            var apiId = Globals.configSettings.AmazonS3ApiId;
            var fileName = !string.IsNullOrEmpty(ChangedFileName) ? ChangedFileName : fileUploadDownloadable.FileName;

            using (var fileTransferUtility = new TransferUtility(new AmazonS3Client(apiId, keyName, Amazon.RegionEndpoint.USEast1)))
            {
                var bucketName = Globals.configSettings.AmazonS3ApiBucketName;                    
                var inputStream = new MemoryStream(File.ReadAllBytes(filePath));
                var key = "images/downloads/" + fileName;                    

                fileTransferUtility.Upload(inputStream, bucketName, key);
            }

---

由于某种原因，当我将代码更改为此时，它开始工作。。我不知道为什么

            var keyName = Globals.configSettings.AmazonS3ApiKey;
            var apiId = Globals.configSettings.AmazonS3ApiId;
            var fileName = !string.IsNullOrEmpty(ChangedFileName) ? ChangedFileName : fileUploadDownloadable.FileName;

            using (var fileTransferUtility = new TransferUtility(new AmazonS3Client(apiId, keyName, Amazon.RegionEndpoint.USEast1)))
            {
                var bucketName = Globals.configSettings.AmazonS3ApiBucketName;                    
                var inputStream = new MemoryStream(File.ReadAllBytes(filePath));
                var key = "images/downloads/" + fileName;                    

                fileTransferUtility.Upload(inputStream, bucketName, key);
            }