[Georgio]

Код:

@echo off

set "dir=D:\Test"
set "list=list.txt"

pushd "%dir%"
2>nul del "%~dp0%list%"
for /f "delims=" %%i in ('"2>nul dir /a-d/b *.xml"') do (
 for /f "tokens=4 delims=_" %%j in ("%%i") do (
  echo %%j>>"%~dp0%list%"
  )
 )
popd

exit /b

[Spacejet]

Премного благодарен!