As far as I understood from TAILS OS website, it is supposed to boot from a USB (using it Live, without installation) and offers you privacy to do whatever you want without leaving usage traces in the host computer. As I explained in another reply, this is absolutely BS because you can do the same with any other Linux distro or even with a Windows Live USB such as Strelec WinPE. Booting from a USB leaves absolutely no usage traces to the host computer. An alternative to a WinPE environment is to create a Windows-to-Go disk. This is an external USB hard disk (or flash drive if at least 64GB) that runs a full Windows system complete with your drivers, applications and games and you won't notice any difference from running the same system installed in the internal SSD. The only difference is that is cannot be upgraded to the next version unless you modify some Registry key to make it "standard" Windows installation. To do that you must place the hard disk internally, since it won't be able to boot from USB if you do it. So you have to remove the (usually SATA) hard disk from the USB case, put it inside, switch it to "standard", upgrade it and then switch it to "Windows-to-Go" again before you can put it back to the USB case and boot it.