To open a ZIP file, you may need to download an appropriate program. On PCs, this is usually preinstalled and is called WinZip. For Mac's you can download this program free of charge on the internet. For mobile devices, e.g. IPad, iPhone and Android devices, there are also suitable apps that you can download for free on your mobile device.
If you're still having issues then don't hesitate to write us a message here and we'll make sure to respond with a solution as quickly as possible!