In case you forgot or lost your Mac password, there are several options to recover it: use Apple ID, OS X Recovery and others.
In this article we try to help you solve a problem that will have happened to several Apple users, that of forgetting your Mac password. Don't worry, there are different ways to solve this concern, for example you can use the Apple ID or restore the default settings. If you have enabled the File Vault disk encryption tool the situation might be more complex, but in any case the problem is easily solvable and let's see how.
Mac password forgotten: use your Apple ID
Let's start from the way that seems to be the easiest for all users, that is to use your personal Apple ID to reset the password of your Mac. For example, if you have forgotten your password and you have already tried to enter the wrong sequences three times, then you will see a message on the screen that says "If you forgot your password, you can reset it using your Apple ID" which means "If you forgot your password, you can use your Apple ID to reset it". That's why in fact you can enter your Apple ID so that your Mac password will reset and you will then be back in control of the tool. It's a very easy and effective method, but unfortunately in some situations it doesn't work. This is the case with FileVault disk encryption option, which needs to be disabled or enabled, but with Recovery Key stored in iCloud.
Reset Max password with OS X Recovery
Let's take a look at a second option, which is valid only in case FileVault encryption option is not enabled. It is a convenient method of resetting the password of any user. You simply need to press Option + R key at boot time, start your Mac in X Recovery mode and use the Password Reset Tool. From this you will understand why it is so important to enable FileVault encryption, because if it is not enabled any user could reset user passwords and take full control of the Mac.
The method we have just described is only effective if the user has not set a password for the UEFI firmware, in which case you should contact an Apple Store for assistance. UEFI firmware password protection is a guarantee in case of theft, that's why the user has absolutely no chance to intervene. If you have more than one user profile on your Mac, it might be useful to log in with a new profile different from the one you forgot the password for. In this way, once you are logged in, you can access the system settings and change the password or create a new profile.
Mac password forgotten, entering FileVault Recovery Key
If the user has decided to enable FileVault disk encryption on the Mac and has not saved the key in iCloud, then the system displays a message asking you to carefully keep a special code, which is a sequence of characters that is the only possible solution in case of password loss. This means that in the specific case where your password no longer works or has been lost, then you have that code available. Therefore, you only need to type it into the password box to unlock the system and proceed with a password change or a change of settings. That's why if you choose not to use iCloud for storing the key, you should absolutely keep this code very carefully, without losing it.
Mac password forgotten, reinstall Mac OS X
We come to the last possible method to recover Mac password, if all the ones we have described before have not allowed you to get back to full control of your device. In this case, the only possible alternative is to reinstall the operating system. It may not be so simple, you may encounter problems and obstacles, for example with FileVault encryption active and a password set for UEFI access the margins for maneuver are very few, the only alternative is to seek assistance. If you try to boot from an external device or in recovery mode, the system displays a padlock under which the password must be entered. The best solution is always to contact Apple support to avoid further problems and inconveniences.