Download links for mac os x el capitan first of all, you would need the download files through which you will be installing mac capitan on your pc via the virtual box so, download all of the files first before getting ahead. Apple released mac os x el capitan that many mac users have been rushing to install on their devices if you wish to join the crowd, below is a quick guide to help you download el capitan from mac app store and you need a mac or virtual mac to create a iso file el capitan is free to download and install it is available on the mac app store.