@BassWrangler
Does not work on my computer, Windows 10. On mine, it cannot be disabled. You can disable functions on it like to keep it from using voice, but there is no way to disable it. Even if you go to Task Manager and disable the process Cortana, it starts itself right back up automatically. It is a Frankenstein App, you cannot kill it. (on my computer)
@240B Yeah, you can...
First though, are you signed in with a local account, or are you signed in with a microsoft account? Because if you are signed in to a MS account, I dunno what this might do...
Settings=>Accounts
If it says 'Local account' under your name, and has an option to 'sign in with a microsoft account instead', you are golden.
If you are signed in to a Microsoft Account, and care about your privacy, I would highly recommend creating a local account instead. Back up your stuff first, and you will likely lose all your settings...
There used to be an option in that case to 'sign into a local account instead' in 'Accounts', but I don't know if that option is still there. ALL of my machines, and ALL of my clients are signed in to local accounts, right off the bat.
But anyway, there's this little gizmo by O&O software called
Shutup10... It is free, and requires no installation... Just download it, save it somewhere where you can find it again, and run it. Under the 'Actions' menu, I use the yellow 'Recommended and somewhat recommended settings', and pretty much all of the Windows spyware is shut off, including Cortana.
Any time you get an update, you'll have to run it again - Sometimes M$ turns stuff back on during the updates... Just fire it up, goto Actions, and select the yellow option again, and close... You may need to suffer a restart, but everything will be turned off again with this easy method.