Hi, I don't want dowload the output files which Galaxy generates, because I don't want to have them in double in my disk. I saw, that the output files are in file_path an I found them. But they have a .dat extension ! In your mailing-list archive I haven't found a solution to transform these extensions. Is it possible to change this with a simple change in a configuration file or in a script file ? Or, must I write my owner script, and if yes, how can I configure Galaxy so that it launches it automatically after one application like MACS for exemple which have a file configuration : macs.xml in the tools directory? Because I've tried to add a line like this in this file : <command interpreter ="perl"> mon scrip.pl</command> I've placed it after the line <command...> which launches the MACS script, but my script seems not work. Thank you. julie