It depends on your av settings. Some people set their av to automatically get rid of files that are considered unsafe. Really another few things to get to the root of the problem. What operating system are you running? What usb slots are you using, have you tried changing them? Have you tried it on other computers? Have you tried to uninstall and reinstall the drivers, resetting the computer between installs? Are all of your permissions right? Delete everything and re-download the files. When a problem occurs it could be so many little things that make a difference. I made a game a few years ago and someone was having problems installing it, and it was as simple as he didn't have wright access to the drive he was installing (was a work computer). The more information you give us the better we might be able to help.