Cortana is a virtual assistant created by Microsoft for the Windows operating system and its associated services such as the Invoke smart speaker, Microsoft Band, Surface Headphones, Xbox gaming console, iOS, Android, Windows Mixed Reality, and Amazon Alexa.

The data from other devices stays until you sign out of Cortana from those individual devices. Once you’ve signed out, Cortana not only deletes all previous data but stops all future data collection as well until you sign back in again. You should note though that signing out does not delete the data that’s saved in the notebook or from your user account which can be found at account.microsoft.com/privacy. All characters that you use in the Cortana search box are sent to Bing, even if you’re signed out of Cortana. If you don’t like that, you can always not use Cortana or hide her instead. Using the search field in File Explorer is another method of not having your data sent to Bing.

1. Sign out of Cortana in Windows 10 to clear data that was created in your computer.

Method One: How to Turn off Speech Services and Typing Suggestions to Clear Dictionary

When you have Cortana enabled, you also have the speech services and typing suggestions enabled because without them Cortana wouldn’t be anywhere near as educated of a virtual assistant as she is now.

You can turn off the speech services and typing suggestions from the Settings application. When you do this, you’ll no longer be able to talk to Cortana, and all speech and dictionary benefits will be lost. You do, however, still get Windows 10’s native dictionary, and speech services that don’t rely on the cloud such as Windows Voice Recognition enabled and working.

1. Open the Settings app and click on Privacy from the Windows Settings menu.

2. Click on Speech, inking, & typing from Privacy’s left menu and then click on the Turn off speech services and typing suggestions button in the right side. (click to enlarge screenshot below)

3. Click the Turn off button.

You can now close the Settings app.

Method Two: How to Clear Personal Data Cortana Knows about you in the Cloud in Cortana Settings

When signed in, you can customize all your permission preferences with Cortana: whether you want her accessing your Calendar, contacts, notebook, location, browsing history, Calendar events, data from messages, and notifications. You can add items to your notebook and Cortana can help you keep track of them, such as your favorite sports teams, places you like to eat, the latest news, and so on. Conversely, clearing your personal data from Cortana will have the opposite effect: the virtual assistant will no longer be able to personalize the experience anywhere near as well—no more recommendations, personalized speech, typing experiences, so forth.

1. Open the Settings app and then click on Cortana from the Windows Settings menu.

2. Click on Permissions & History from Cortana’s left side menu and then click on Change what Cortana knows about me in the cloud from the right side of the Settings window. (click to enlarge screenshot below)

3. Scroll down Cortana’s flyout and click on the Clear button under the Clearing your personal info heading.

4. You should see the Your recommendations are now cleared in a green text when it’s complete.

You can now close Cortana’s settings.

Method Three: How to Clear Your Device History in Cortana Settings

When enabled, Cortana uses the My Device History feature to collect information across all devices that you use with the one Microsoft account to help create better search results when you use her. My Device History is enabled by default in Windows 10, so you’d need to venture into the Settings app and turn the toggle off if you wanted it off. Alternatively, you can also clear the My Device History from the same area so Cortana doesn’t have any data stored.

1. Open the Settings app and click on the Cortana entry from the Windows Settings menu.

2. Click on Permissions & History from Cortana’s left menu and then scroll down the right side of the window until you can see the Clear my device history button. (click to enlarge screenshot below)

You can now close the Settings app.

That’s all.