Imagine this current scenario without two-step verification. You forget your phone and someone cleverly takes out the SIM card. He or she then takes a new device, inserts your SIM card and installs WhatsApp on it and takes total control.
WhatsApp will think that you might have simply changed your smartphone or got a new one. On the other hand, you will have no clue that someone was already busy with your personal WhatsApp account. The situation might get worse if you happen to lose your smartphone.
WhatsApp two-step verification aims to prevent this. The app simply wants to verify that the person in possession of your SIM card is really you or not.
To activate two-step verification, to go Settings > Account > Two-step verification > Enable. Enter a six digit passcode and confirm the same. Be sure to remember the passcode. After that you must enter your valid email. “This email address will allow WhatsApp to send you a link via email to disable two-step verification in case you ever forget your six-digit passcode, and also to help safeguard your account,” explained WhatsApp in a post.
After two-step verification has been activated, the next time your SIM card is inserted in a new device to access WhatsApp, it will ask for this six-digit passcode. If the code doesn’t match, “your number will not be permitted to reverify on WhatsApp within 7 days of last using WhatsApp without your passcode,” said WhatsApp.
In case, you don’t remember the passcode, your email ID will come handy. Thus, it is very important to provide the correct email ID while enabling two-step verification.
However, if you cannot provide the passcode or the email ID, your WhatsApp account will be inaccessible for 7 days. “After which, 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,” alerted WhatsApp.
“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,” it added.