hi there I am new and I have a question
I want to let the user of my site download a file. But I want to put it on a folder on their machine instead of popping the window, open - save. Also I want to check if the folder was already created on his computer if not create it and download the file into that folder.

You can't

you cant do that like chrishirst says

you can do it so you can click a link and the folder will download but it will ask you were you want it putting etc etc

You might look into some sort of MSI builder or something the user can download which would provide an installation wizard. What sort of website would require a user to download a file into a specific directory? Is it for malicious purposes?