title: List files in one folder structure which aren't in another
body: <p>Just got a new phone and have temporarily copied the old ones files onto my PC C:\OldPhone\</p>
  
  <p>On my PC are all my photos, in various folders below D:\Photos.</p>
  
  <p>I want some code to list all the .jpg files below C:\OldPhone\ which are not anywhere below D:\Photos\</p>
  
  <p>Does that make sense? Just to stress, the folder structures are not identical and I don't mind where the file is, just as long as it's there. Filename comparison would do for starters, option to add size would be a bonus!</p>
  
  <p>CMD, VBS or powershell would be good, but anything visual studio can cope with would be ok too.</p>