Don't like Windows 10? Go back, but you only have 30 days!Last Updated: 5/20/16
Don't like Windows 10? You can uninstall it and go back to Windows 7 or Windows 8.1, but you only get 30 days to decide. After 30 days your old version of windows is erased.
Going back to Windows 7 or Windows 8.1 - Windows Help -
Why Windows 10 Upgrades Go Wrong, and How to Avoid It - The New York Times