>Greetings,
> I'm making a backup program in vfp6.0, how or what command can I use to be able to know the size of a folder?

You'd need to recurse the subfolder tree and determine the sizes; the easiest method would most likely employ the WSH Scripting.FileSystemObject COM server, which contains some functionality you might find useful. See my sig block for links to several resources on the WSH.