How to Change a Forgotten iMac Password

Setting a password on an iMac computer is important to protect the computer's contents from unauthorized access. When setting up an iMac computer, a master password can be assigned to the iMac administrator account, and sub-user accounts can also be password-protected. If sub-user passwords are forgotten, they are easily changed; but changing the iMac administrator's account takes a bit more work.

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User Passwords

Step

Boot up the computer and log in to the administrator's user account.

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From the Apple menu, select "System Preferences."

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When the System preferences window opens, look in the "System" pane, and choose "Accounts."

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Click on the lock icon if it is locked, and enter the original iMac administrator's password.

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In the Account Pane, click on the user account of the password you wish to change. In Mac OS X v10.3 and v10.4, click the "Reset Password" button. In Mac OS X v10.5 and later, click the "Change Password" button.

iMac Administrator Password

Step

Insert the Mac OS X installation disc into the optical drive and restart the iMac, holding down the "C" key while it starts. Release the "C" key when you hear the startup tone.

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Alternatively, insert the Mac OS X installation disc into the drive and go to the Apple menu. Select "System Preferences," then "Startup Disc" to select the disc you just inserted to start up your iMac.

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When the "Installer" screen appears, select the appropriate language, then click the button to continue.

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Select "Reset Password" from the Installer Menu for Mac OS X v10.3, or "Reset Password" from the "Utilities" Menu for Mac OS X v10.4 or 10.5.

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Choose the Macintosh HD volume by highlighting it. Select the original administrator's user name. Enter your new password, and click "Save." Quit the Mac OS X installer and restart your iMac.