How to Fix "Your Clock is Ahead" Error on MAC

The date or time may need to be reconfigured, or you may be using a custom format.

Check the date and time settings.

1. Choose Apple menu> System Preferences, then click Date & Time.

2. Enter your admin password to unlock the settings. (The setting is grayed out if it is locked).

3. Make sure that "Set the date and time automatically" is selected in the Date and Time section, and that your Mac is connected to the Internet. Your Mac can remember the current date and time from the network time server.

Check time zone settings

1. Select Apple menu> System Preferences then click Date & Time

2. Click the lock icon in the corner of the window and then enter your administrator password to unlock the settings .(It's grayed out when it's locked).

3. In the Time Zones panel, make sure "Set the time zone automatically based on my current location" is selected and your Mac is connected to the Internet.

4. If you see a message that an updated time zone is available, restart your Mac to start installation.

Check your language and region settings

1. Select Apple menu> System Preferences, then click Language & Region.

2. Make sure the Region menu is set correctly for your region.

3. Use the Time Format check box to control whether your Mac displays the time in 24-hour format.

Also, read How to Fix "Your Clock is Ahead" Chrome Error Windows 7 on My Geek Score.