Make sure:
When using your authenticator app to get a passcode:
  • If you have more than one account paired with your authenticator app, make sure you select the passcode that corresponds to the account you are trying to access.
  • The passcode changes approximately every 30 seconds. When prompted to authenticate, enter the most recent passcode.
  • A passcode can only be used once.
  1. Sign on to your Mac machine.

    A screen capture of the Mac login page.
    You'll see the Authentication window, prompting you to enter a passcode.

    Screenshot of the Authentication window showing the passcode field.

  2. Launch your authenticator app.
    The authenticator app displays a one-time passcode for your account.

    Screenshot of a typical authenticator app.

    This example shows the Google authenticator.

  3. Enter the passcode into the Authentication window, and then click Sign On.
    You'll see the green checkmark indicating authentication is successful and you are signed on to your machine.

    A screen capture of the Mac login desktop following successful sign on.