My question is pretty simple. How do I update my Windows 8 Pro which is activated via KMS to Windows 8.1. I am unable to see Windows 8.1 update in my Store. I read it somewhere on the Internet that KMS activated Windows 8 aren't getting update via store. Is it true? How can I update (not reinstall) Windows 8 to Windows 8.1 without loosing any of my personal and system data. Thank You.