How do I change the header.jpg located in bp-social>_inc>images>header.jpg?

I tried to FTP a new image to that location, but it completely wiped out the little box that originally had the image of a boy with a box on his head.

Being that that box is wiped out, am I going to have to do something else to restore it? I tried going back to the default settings in the Theme Options, but that did not work.