DavidR
9
Check out the image, effectively you have to have two windows explorer window open. One open at the folder the file you want to upload, the other at a blank window.
Copy and paste this url into the address bar of the blank one.
ftp://ftp.avast.com/incoming
Now drag the file you want to upload from one explorer window, into the right side of the other window.
EDIT: code url edited, was incorrect.