If you upgrade to two-factor authentication, you can’t log in to your Mac with an iCloud password<article>
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<p>A few releases of what was then called Mac OS X, Apple added an option that seemed a convenient way to reduce the number of passwords you had to remember. While setting up a system (or later via the Users & Groups system preference pane), you could opt to use the password for your iCloud account to “login and unlock” your Mac.</p><p>The ostensible idea was to make it easier for regular human beings who didn’t want to maintain multiple strong passwords to protect their stuff to use a single one in two related locations. While it increases the risk to re-use passwords, this seemed like a reasonable tradeoff for someone who picked a good password.</p><p>At some point, Apple thought the better of the option, either because of the risk or because of the integration with its newer login validation system, which I recently discussed. Starting in El Capitan 10.11.4, the option to switch to use an iCloud password for login has disappeared. It used to be available after setup when you clicked Change Password while viewing an account in the Users & Groups preference pane.</p><p class="jumpTag"><a href="/article/3125098/security/if-you-upgrade-to-two-factor-authentication-you-cant-log-in-to-your-mac-with-an-icloud-password.html#jump">To read this article in full or to leave a comment, please click here[/url]</p></section></article>
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If you upgrade to two-factor authentication, you can’t log in to your Mac with an iCloud password
