@ECHO OFF
SETLOCAL
FOR %%n IN (*) DO ECHO "%%n"|FINDSTR /U "! ^" >nul&IF ERRORLEVEL 1 (
 SET "name=%%~nxn"
 SETLOCAL enabledelayedexpansion
 FOR %%a IN (a b c d e f g h i j k l m n o p q r s t u v w x y z
  ) DO SET "name=!name:%%a=%%a!"
 REN "%%~fn" "!name!"
 endlocal
)

GOTO :EOF