Another Microsoft Bug - Directory.CreateDirectory() will not work on a virtual directory

My app will upload pictures to the server, then display it back to the client, showing the pictures just uploaded. However, The function "Directory.CreateDirectory(virtualDirectory);" will not create a directory. Here is the sample code you can put a break point to reproduce and track the bug:

            string absolutePath = Path.Combine(_environment.WebRootPath, "images\\Products");
            string virtualPath = "\\images\\Products";
            string absoluteDirectory = Path.Combine(absolutePath, ProductId.ToString());
            string virtualDirectory = Path.Combine(virtualPath, ProductId.ToString());
            bool tmpA = Directory.Exists(absoluteDirectory);
            bool tmpV = Directory.Exists(virtualDirectory);
            if (!Directory.Exists(virtualDirectory))
            {
                Directory.CreateDirectory(virtualDirectory);
            }

If I replace the "Directory.CreateDirectory(virtualDirectory);" with the "Directory.CreateDirectory(absoluteDirectory);", a directory could be created. Then why bother using a Virtual Directory? Why not just using an absolute path? The reason is when I display the picture back, absolutePath will not work. The

<img src="@Url.Content(item.Path)" height="150" />

will only work on Virtual Path.

To summarize: when I upload a picture, I have to use Absolute Path in order to get the directory created; when I display this picture back, I have to use Virtual Path. My current work around is to keep both paths.