Cortana is part of the Windows 10 experience in the locales where she is available. This means Cortana can't be entirely turned off. For Cortana to work well, she needs to be integrated into the operating system. If you don’t want this functionality available to you follow these steps to hide Cortana from the taskbar:
- On the taskbar, right-click (or press and hold) Cortana, hover over Cortana on the menu, and then select Hidden from the side menu. This will also remove the search box from your taskbar. We don’t recommend hacking registry settings or similar measures as this can make your operating system unstable or crash.
You can review and control exactly what personal information Cortana can access by clicking into the search box and selecting Settings on the left pane. You can also search "Cortana settings" in the search box on the taskbar, and select Cortana & Search settings from the results.
Note: Cortana is removed from the Windows 10 Education and Windows 10 Pro Education editions. See Windows 10 editions for education customers for more info.