I have 2 solutions:
All files are in the same folder
run the following from command prompt on that folder:
for /f "delims=¯" %i in ('dir /b /on') do ren "%i""._%i"
complete solution when there are files in subfolders AND when you wanna to replace the "n" first characters with a string you want :D
- create a batch file with the following command
- change variable parameters to what you want
path: put inside""the root path of your files (e.g. "C:\documents and settings\user\desktop\new folder"numfirstchars2replace: put a number with the first characters to replace (in your case, 2)str2put: put a string to be added as a prefix of the new filename (in your case,._)
- run it in a folder different from where the files are
@echo off::only to tell user what this bat are doingecho.1.initializing...::enable that thing to allow, for example, incremental counter in a for loop :)echo.- EnableDelayedExpansionSETLOCAL EnableDelayedExpansion::variablesecho.- variables:: - place here the absolute root path of your filesset path="put here where are the root folder of your files"set pathbak=%cd%set numfirstchars2replace=2set str2put=._::go to %path% and its driveletterecho.- entering the path you wantfor /f "delims=¯" %%i in ('echo.%path%') do %%~dicd %path%::search all subfolders and save them to a temp fileecho.- searching for subfoldersecho.%path%>%temp%\tmpvar.txtfor /f "delims=¯" %%i in ('dir /s /b /on /ad') do echo."%%i">>%temp%\tmpvar.txt::execute command for root folder and all found subfoldersecho.echo.2.executing...for /f "delims=¯" %%i in (%temp%\tmpvar.txt) do ( cd %%i echo.- in folder: %%i for /f "delims=¯" %%j in ('dir /b /on /a-d') do ( set newname=%%j set newname=!newname:~%numfirstchars2replace%,1000! echo.- renaming from "%%j" to "%str2put%!newname!"... ren "%%j""%str2put%!newname!" ))echo.echo.3.exiting...::return to %pathbak% and its driveletterfor /f "delims=¯" %%i in ('echo.%pathbak%') do %%~dicd %pathbak%@echo on