A workaround to delete long file names from http://blogs.msdn.com/b/bclteam/archive/2007/03/26/long-paths-in-net-part-2-of-3-long-path-workarounds-kim-hamilton.aspx

deleting with win32 api

using System;
using System.Runtime.InteropServices;

[DllImport("kernel32.dll", CharSet = CharSet.Unicode)]
[return: MarshalAs(UnmanagedType.Bool)]
internal static extern bool DeleteFile(string lpFileName);

// This code snippet is provided under the Microsoft Permissive License.
public static void Delete(string fileName) {
    // call it with a file name prefixed by \\?\:
    string formattedName = @"\\?\" + fileName;
    DeleteFile(formattedName);
}