How to turn on the Two-Factor Authentication.
IMPORTANT!
Two-factor authentication is currently available to iCloud users with at least one device that’s using iOS 9 or OSX El Capital or later. Learn more.
On your iPhone, iPad or iPod touch:
Go to Settings > [your name].
If you’re using iOS 10.2 or earlier, go to Settings > iCloud and tap your Apple ID.
Tap Password & Security. If asked, enter your Apple ID password.
Tap Turn On Two-Factor Authentication.
On your Mac:
Go to Apple menu () > System Preferences.
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Click iCloud, then click Account Details. If asked, enter your Apple ID password.
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2. Click on the Security tab. Then click on Turn On Two-Factor Authentication.
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How to turn off the Two-Step Verification
Visit URL: https://appleid.apple.com/.
Sign in to into your account.
In the Security , section, look for two-step verification, then see if the feature is off or on. If off, click Edit.
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4. Click on Turn Off Two-Step Verification.
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5. Create new security questions and verify your date of birth.
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