Once you start using a Microsoft account to sign into Windows, you have to use a password every time. If you have a work account, you’ll need a password for that, and you probably have to change it regularly and even if you just have a local Windows account, it’s a good idea to have a password to keep your account safe. That doesn’t mean you have to remember a complicated password, though the new Windows Hello interface makes it easy to log in securely with biometrics.
Hello keeps the previous representations it has of you, so if you shave off the beard or go back to your old glasses, it should recognize you without you needing to re-enroll, Windows Hello can tell which way your head is facing, but it doesn’t store that in the template – and it shouldn’t matter if the lighting changes, because what it’s looking at is the shape of your face rather than the way it looks.
Open the Settings app and choose Accounts, Sign-in options. You have to create a PIN first to unlock the Hello options – you need that in case your face or fingerprint isn’t recognized – for example if you cut your finger or have a bandage on it, or it’s just too cold and your finger isn’t recognized properly, you can still get to your account. You can always choose to use the PIN, and if Windows Hello can’t recognize your face or fingerprint five times, you have to use the PIN. It’s a PIN rather than a password, because a PIN is only ever saved on your PC – your password might get hacked in a variety of ways.
Click the Add button under PIN and enter a PIN (which means entering your password as well, to stop someone else locking you out of your PC), then you’ll see the Windows Hello options for whichever biometrics you have. If you have the right camera you’ll see the controls to set up your face recognition – if you have a fingerprint reader, you’ll see the buttons to enroll one or more fingerprints. Click Set-up to read an explanation of Windows Hello, then get in the right position for your camera and click Get Started; you need to enter your PIN to prove it’s your face you’re enrolling. The recognition takes only a few seconds – and you can see your face on-screen to check. Once it’s done, you can click Improve Recognition if you want to take another snapshot, perhaps without your glasses; that takes much longer, because it scans more landmarks on your face – up to two minutes in some cases.