DeleteFilesModifiedBeforeDateTime.ps1

$rootPath = "D:\Advertiser"
$deleteFileBefore = New-Object -typename System.DateTime -argumentlist (2013,12,25,0,0,0)

$root = New-Object -typename System.IO.DirectoryInfo -argumentlist $rootPath

foreach ($file in $root.GetFiles(“*”, [System.IO.SearchOption]::AllDirectories))
{
    if ($file.LastWriteTime -le $deleteFileBefore)
    {
        echo ("Deleting", $file.FullName -join " ");
        $file.Delete();
    }
}

foreach ($subDir in $root.GetDirectories(“*”, [System.IO.SearchOption]::AllDirectories))
{
    $subDir.Refresh()
    if ($subDir.Exists)
    {
        $filesCount = $subDir.GetFiles(“*”, [System.IO.SearchOption]::AllDirectories).Length;
        if ($filesCount -eq 0)
        {
            echo ("Deleting", $subDir.FullName -join " ");
            $subDir.Delete($True);
        }
    }
}