Topic: 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 net...