With two-step authentication, it is not enough to have the username and password of your account to connect to it from an unknown device: you must also enter a one-time code sent by SMS on your smartphone.
The theft of Facebook accounts doesn’t just happen to others. It is likely that at least one of your friends on the social network has experienced this mishap. It is therefore essential to protect personal data and files that are hosted online. Most services now offer a new security feature called double authentication or two-step identification. This occurs as soon as you try to connect from a computer or mobile that is not among the certified devices.
To find out if your favorite online services have such a feature, go to https://twofactorauth.org/ and enter the name of the store or social network in the search box.
Secure Dropbox
To enable two-factor authentication on Dropbox, log into your account management interface from an Internet browser. Once identified, click on your avatar and point to the Settings command.
Activate the Security tab, then in the Two-step verification section, set the Require security key or code switch to the On position. Then choose the sending of the security code (by SMS for example by indicating your mobile number).
Protect a Google Account
Go to your Google Account dashboard. Click on your avatar then on My account. Then point to the Connection and security heading, scroll down to the Password and connection method section. Activate the Two-step validation option.
Follow the instructions of the wizard to set up the double lock and select the mobile that will receive the security codes.
On the Facebook side
Launch the Facebook app on your smartphone. Tap the Menu button (three horizontal lines in the corner of the screen) then Settings, Account settings and Use two-factor authentication.
Check the Two-Factor Authentication option and enter your account password. Touch Continue, Start Setup. Enter your mobile number, then enter the code received by SMS to activate double authentication.