How to write a batch to run a program to change all the FILES in ONE folder to a different FORMAT?
For example, to change one file, I would type:
A.exe B.xxx B.yyy
I don't want to just change the extension, but have the program convert the files. 
it seems that you want to write a batch file to change a dbf file to an xls file etc

i do not  think so!Huh? I have a folder FULL of textures for a game that come in a custom format and i want to convert them to tga files to edit in photoshop. The conversion program works from the command line only and converting 100 textures one by one would be a major pain.i could do it dbase with this sort of loop arrangement

copy all the files into a temp directory

find the first file in the new directory

exercise the command line jargon

move the NEWLY formatted file to the original directory

delete the first file

call the batch again

you will need a counter in there or else watch the dos stuff till you get error messages.

- i am sure there is a better way, but this will probably work