分快上传，提示Thespecifieduploaddoesnotexist.

学习的 千鸟前辈的代码 大文件分块上传代码  传递的参数是
fileLength=FileUpload1.PostedFile.ContentLength, fis=FileUpload1.PostedFile.InputStream

    public static string UploadFile(int fileLength, Stream fis,string strFielName)
    {
        // id
        string strId = System.Configuration.ConfigurationManager.AppSettings["AliId"];
        // Key
        string strKey = System.Configuration.ConfigurationManager.AppSettings["AliKey"];


        string strEndpoint = System.Configuration.ConfigurationManager.AppSettings["AliUrl"];


        string bucketName = System.Configuration.ConfigurationManager.AppSettings["bucket"];


        OssClient client = new OssClient(strEndpoint, strId, strKey);
        InitiateMultipartUploadRequest initiateMultipartUploadRequest = new InitiateMultipartUploadRequest(bucketName, strKey);
        InitiateMultipartUploadResult initiateMultipartUploadResult = client.InitiateMultipartUpload(initiateMultipartUploadRequest);
        // 设置每块为 5M
        int partSize = 1024 * 1024 * 5;
        // 计算分块数目
        int partCount = (int)(fileLength / partSize);
        if (fileLength % partSize != 0)
        {
            partCount++;
        }
        // 新建一个List保存每个分块上传后的ETag和PartNumber
        List<PartETag> partETags = new List<PartETag>();


        for (int i = 0; i < partCount; i++)
        {
            // 跳到每个分块的开头  
            long skipBytes = partSize * i;
            fis.Position = skipBytes;
            //fis.skip(skipBytes);    
            // 计算每个分块的大小
            long size = partSize < fileLength - skipBytes ? partSize : fileLength - skipBytes;
            // 创建UploadPartRequest，上传分块
            UploadPartRequest uploadPartRequest = new UploadPartRequest(bucketName, strFielName, initiateMultipartUploadResult.UploadId);
            uploadPartRequest.InputStream = fis;
            uploadPartRequest.PartSize = size;
            uploadPartRequest.PartNumber = (i + 1);
            UploadPartResult uploadPartResult = client.UploadPart(uploadPartRequest);
            // 将返回的PartETag保存到List中。
            partETags.Add(uploadPartResult.PartETag);
            // 关闭文件
            fis.Close();
        }
        CompleteMultipartUploadRequest completeReq = new CompleteMultipartUploadRequest(bucketName, strKey, initiateMultipartUploadResult.UploadId);
        foreach (PartETag partETag in partETags)
        {
            completeReq.PartETags.Add(partETag);
        }  
        //完成分块上传  
        CompleteMultipartUploadResult completeResult = client.CompleteMultipartUpload(completeReq);


        return completeResult.ETag;
    }




在 UploadPartResult uploadPartResult = client.UploadPart(uploadPartRequest);  这一步的时候 提示：
The specified upload does not exist. The upload ID may be invalid, or theupload may have been aborted or completed.
错误  求大神们指点！！！！！！