I have to rename a set of file with name like this: CR.1.3.46.670589.26.300060.4.20030929.171535.817.0 or CR.1.3.46.670589.26.300060.4.20030929.172025.818.0 in files with name like 817 and 818 and so on. So, I have to delete the first 45 characters and the extension .0 . I read the program below in this forum: @echo off if "%1"=="GoTo" goto %2 if not "%OS%"=="Windows_NT" goto eof %comspec% /v:on /c %0 GoTo start goto eof :start echo. echo This program will rename all files from the current directory, echo and possibly from its subdirectories, following a certain rule. echo. echo Press any key to VIEW the renaming process . . . pause > nul echo Processing . . . type nul> %temp%.\process.bat :: To include the files under subdirectories from current :: directory on the renaming process, add the string ' /R' :: after the string 'for' on the next line, so it becomes :: 'for /R' (don't forget the space between the strings) for %%F in (*.*) do ( set ORIG=%%~nF set ORIG=!ORIG:-=! set FILE=!ORIG:~3,-4! set EXT=!ORIG:~-4,-1! if not "!FILE!"=="" if not "!EXT!"=="" ( echo REN "%%F" "!FILE!.!EXT!">> %temp%.\process.bat ) ) echo. type %temp%.\process.bat |MORE echo The above process is NOT reversible. echo. set CH= :loop set /P CH=To you wish to execute the above process [Y/N]? if /i "%CH%"=="Y" ( call %temp%.\process.bat echo. echo Operation done. del %temp%.\process.bat goto eof ) if /i "%CH%"=="N" ( echo. echo Operation aborted del %temp%.\process.bat goto eof ) goto loop :eof Could I modify this program and if yes, how could I modify it to obtain what I need? Thank you very much

If you have to rename files as those you posted, .0 extension and fixed format filename, it is more practical you try the following: @Echo Off For /F "tokens=*" %%I in ('Dir /B %~f1.\*.0') Do Call :REN %~f1 %%I GoTo :EOF :REN Set FName=%~n2 Echo Ren %~f1.\%2 %FName:~45% GoTo :EOF Typing "MyRen Folder" (where MyRen is the name of the batch and Folder the directory storing the files .0) you accomplish your job. When sure the script works as you planned, activate it by removing the Echo in front of the Ren command. Good Work