I had a directory of filenames like this: rank(all)_so2_1hr_conc_A_2p5h10.dat and wanted to crop rank(all)_so2_1hr_conc_ I discovered a nice way to do this was by using this: @echo off for %%i in (*.dat) do (set fName=%%i) & call :rename goto :eof :rename :: Crops the 1st 23 characters of fName ('rank(all)_so2_1hr_conc_'): ren %fName% %fName:~23% goto :eof This results in this: A_2p5h10.dat Now I need to convert this to: A_2p5h100.dat Notice 'h10' needs top be 'h100'. Can you please suggest a routine that will add the '0' in the middle of the file name? There are hundreds of file names in the directory that need to have this conversion. Thanks, Tommy

well, I would be using unix stuff to do it - you can grab unixkit for windows & it'll give you this stuff. ls | cut -d'_' -f5- should give A_2p5h10.dat Add: | awk -f"." '{print $1"0.dat"}' Should do it

Neither unix nor XP are DOS. [hint: this is the DOS forum] ===================================== If at first you don't succeed, you're about average. M2