The first time you launch Easy Hanzi, the software checks if you have a Chinese font installed. If not, you will be prompted with a link to a page containing instruction on how to install one. If, for some reason you missed this link, it won’t be shown again (this is because the font check is slow and, most of the time, unnecessary). So in case you missed it, here is the link:
I thought about writing this kind of page myself but it probably wouldn’t have been as complete and detailed as Wikipedia. If something is unclear though, feel free to contact me.