Microsoft started rolling out its two-step verification process on April 17. Also known as two-factor authentication or two-step authentication, the process strengthens your account security by requiring you to enter your password (step 1), then a security code (step 2). The security code can be sent to you by e-mail, SMS, or phone call, or you can use an authenticator app on your mobile device.
Enabling two-step verification on your Microsoft account will enable it across all Microsoft services that currently support two-step verification, like Windows, Outlook.com, Office, and SkyDrive. If you're interested in trying it out, here's how to get started:
Enable two-step verification
Step 1: Go to https://account.live.com/proofs/Manage and make sure that you've added an alternate e-mail address and provided a phone number (preferably your mobile number so it can receive SMS messages) to your Microsoft account.
Step 2: Click on the "Set up two-step verification" link.
Step 3: Follow the setup process until you reach the end, then click "Done." You may be asked to provide a verification code, sent to either your phone via SMS or to your alternate e-mail address, before you can complete the two-step setup. Once it's complete, you should receive an e-mail confirmation from Microsoft sent to your alternate e-mail address.
Pair an authenticator app with your Microsoft account
You can get security codes by e-mail, phone call, or SMS, but an even easier way is to use an authenticator app on your mobile device. Authenticator apps, like Google Authenticator, run locally on your device and work even if your device doesn't have an Internet connection. To use an authenticator app, you first have to pair it with your Microsoft account.
Step 2: Go back to your Microsoft account security info page and click on the "Set up" link under Authenticator app.
Step 3: Launch your authenticator app, then scan the bar code on the screen.
Step 4: When the security code appears in the authenticator app, enter it in the box, then click on the Pair button.
Using two-step verification
Once you've enabled two-step verification on your Microsoft account, logging in to your Microsoft services will require your account password and a security code.
If you have an authenticator app paired, it'll request the code from the authenticator app. If you prefer to use a different verification option, click on the link to the right of the code box to choose a text message, phone call, or e-mail.
If you log in regularly using the same computer or device, you can check the box next to "I sign in frequently on this device. Don't ask me for a code" before you log in. This will add the device to your account as a trusted device and you won't be required to enter the security code every time you log in from that device.
Lastly, some apps and devices don't support security codes. In those instances, you can go to the security info page and create an app password to log in.
Keep in mind that Microsoft's two-step verification is still rolling out, so if you don't see the option yet, check again later.