public static void SetBlobMD5(string containerName, string blobName, string md5)
{
var client = AzureHelper.GetCloudBlobClient();
var container = client.GetContainerReference(containerName);
var blob = container.GetBlockBlobReference(blobName);
blob.FetchAttributes();
blob.Properties.ContentMD5 = md5;
blob.SetProperties();
}