We currently own a desktop PC that came preloaded with Windows 7, already activated and everything. But I recently acquired a little tiny laptop with no optical drive. It ran perfectly well on it's preloaded Windows XP, until I bricked it that is. Instead of trying to find a way to reinstall XP, I went straight to Windows 7. I downloaded the ISO files for Windows 7 Home Premium and created a bootable installation drive on a USB flashdrive, and installed Home Premium on the netbook. I then used the product key from the sticker on the side of my desktop tower, and it started and has been working since then. But everyday it pops up a window saying that I need to activate my system, and to enter a product key. It says I have 19 days to activate my system. So since my old key didn't work, I'm assuming I wasn't supposed to use my old key? And that leads me to believe what I didn't isn't strictly legal? So was it illegal, and if so, what am I supposed to do to when my 19 days are up?