Rename PDF files in specific date format

Hello Martin, Sorry for have delayed on this one...

well, just create a txt file and name it as you like but using a .bat extension

then place it inside the foler where the file are named as you described above

copy paste the code below, and once saved, double clik on the bat file... the DOS will handle the magic

be aware to copy saved the old file, just in case of an unexpected error...

let me know if that fits your needs

have a pleasant day

birnou

@ECHO off  

SETLOCAL EnableDelayedExpansion

SET map[January]=01

SET map[February]=02

SET map[March]=03

SET map[April]=04

SET map[May]=05

SET map[June]=06

SET map[July]=07

SET map[August]=08

SET map[September]=09

SET map[October]=10

SET map[November]=11

SET map[December]=12

FOR %%a in (*.pdf) do (

  SET OLD_FILE_NAME=%%~na

  FOR /F "tokens=1,2,3 delims=,. " %%P in ("%%a") do  ( 

    SET M=!map[%%~nP]!

    SET D=000000%%~nQ

    SET Y=%%~nR

    SET NEW_FILE_NAME=!Y!_!M!_!D:~-2!_!D:~-2!!M!!Y!

    RENAME "!OLD_FILE_NAME!.pdf" "!NEW_FILE_NAME!.pdf"

  )

)

ECHO DONE

PAUSE