@echo off
:seleccionar
pause
:inicio
For %%x in (C:\Users\"user"\Music) do call :Rename %%x %%~xx
goto :EOF
:Rename
set Orig=%1
set Exte=%2
set /a cnt+=1
if %cnt% LSS 1 set goto :seleccionar
if %cnt% GEQ 1 set New=%cnt%%Exte%
ren %Orig% %New%
@echo off
:seleccionar
SET /P Ruta=Indique la ruta...
pause
:inicio
For %%x in ("C:\Users\%Ruta%\Music") do call :Rename %%x %%~xx
goto :EOF
:Rename
set Orig=%1
set Exte=%2
set /a cnt+=1
if %cnt% LSS 1 set goto :seleccionar
if %cnt% GEQ 1 set New=%cnt%%Exte%
ren %Orig% %New%