How to remove Cortana from Windows 10
If you have Windows 10 Professional or Enterprise you will be able to shut down Cortana by simply typing gpedit.msc in the search box to open the Group Policy Editor. Navigate to Local Computer Policy > Computer Configuration > Administrative Templates > Windows Components > Search. Double-click on the policy named Allow Cortana.
When the policy window appears just click Disable. That’s all you need to do shut down Cortana.
However, if you are using Windows 10 Home, you will need to edit the Windows Registry. Do not tackle this step unless you have experience editing the Registry. Additionally, you should set a restore point now in case things go sideways.
So if you are confident about working in the Registry Type Regedit into the search box in and open the Registry Editor. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\Windows Search. That final key (Windows Search) may not be present in the Registry. If it is not present, right-click the Windows directory and select New > Key. Name it Windows Search.
Now select that new key. In the right-hand pane, right-click and select new DWORD and name it AllowCortana. Then right-click that value and make sure it’s set to 0, which means “off”.
Now sign out and back in again or restart your PC and you should notice that Cortana has been replaced with a generic search box.