Removing duplicate files with Powershell

Question

I have several thousand duplicate files (jar files as an example) that I\'d like to use powershell to

1. Search through the file system recursively
2. Find the

Answer 1

Keep a dictionary of files, delete when the next file name was already encountered before:

$dict = @{};
dir c:\admin -Recurse | foreach {
  $key = $_.Name #replace this with your checksum function
  $find = $dict[$key];
  if($find -ne $null) {
    #current file is a duplicate
    #Remove-Item -Path $_.FullName ?    
  }
  $dict[$key] = 0; #dummy placeholder to save memory
}

I used file name as a key, but you can use a checksum if you want (or both) - see code comment.