WhatsApp is rolling out two-step verification to all its users on Android, iOS, and Windows after testing the feature since last November. It's an optional feature—disabled by default—meant to boost the security of your messaging account. When enabled, you'll be required to input a six-digit code of your choice when you're asked to verify your phone number.

Enabling two-step verification is easy: just navigate to the Account page under Settings in WhatsApp and choose Two-Step Verification. After you make your six-digital authentication code, you'll be asked for it every seven days as well as whenever you need to verify your phone number (when you register your account on a new phone, for example). You can also add an e-mail when you enable two-step verification, which WhatsApp will use to e-mail you a link to disable the feature if you ever forget your code.

But let's say you forget your code and didn't enter a recovery e-mail into WhatsApp. In this case, you'll be able to log back in to WhatsApp only after seven days of your last use of the app. According to WhatsApp, however, there will be consequences for your messages and account in this case. "After these seven days, your number will be permitted to reverify on WhatsApp without your passcode, but you will lose all pending messages upon reverifying—they will be deleted," WhatsApp's FAQ page states. "If your number is reverified on WhatsApp after 30 days of last using WhatsApp, and without your passcode, your account will be deleted and a new one will be created upon successfully reverifying."

So while this is a good feature to help keep your account safe from unauthorized access, WhatsApp is serious about the necessity and validity of your six-digit code. There's no way to prevent WhatsApp from asking you for your six-digit code every few days, either, so you must remember it to keep using WhatsApp. It's worth it to enter an accurate e-mail address so you're not totally locked out for days—and so you avoid losing messages or your entire account.