As usual over the last few weeks of installing Windows 10 and running into a million crazy conflicts. I thought the cat was in the bag. I had been using my desktop for about 5 days and everything was great. Same with my laptop, or so I thought. Turned the laptop on today and had a sign saying I must activate windows. Tried to activate and got the answer that my activation code was already in use and to visit windows store and buy a copy of Windows 10. I have had this copy through thick and thin for 4 months now and was never hit with this problem. Although it doesn't surprise as things were going too smoothly.My Gateway desktop was not supposed to be compatible with Windows 10, I did the upgrade, and after some hassals with drivers and missing start menu, got the desktop running like a swiss watch. Now, 5 days ago my laptop was running great finally and then I turn it on today and have to activate windows that fails. Any Idea or suggestions? You guys are great. I am having Windows 10 problems on an Acer 5253 laptop that was running Windows 7 and the did the upgrade through Microsoft. How can it be that a comptuter NOT slotted for upgrade beats a legal Windows 10 download? Any ideas on how to figure this mess out?