@echo off
setlocal EnableExtensions EnableDelayedExpansion
pushd %1
set FileSize=-1
set FileName=""
for /f "tokens=*" %%I in ('dir "%TargetDir%" /o:sn /b /a:-d') do (
if !FileSize! EQU %%~zI (
fc /b !FileName! "%%~fI">nul
if not errorlevel 1 echo del "%%~fI"
) else (
set FileSize=%%~zI
set FileName="%%~fI"
)
)
popd