{"id":58763,"date":"2020-02-20T13:00:00","date_gmt":"2020-02-20T19:00:00","guid":{"rendered":"https:\/\/eshop.macsales.com\/blog\/?p=58763"},"modified":"2020-02-25T15:03:03","modified_gmt":"2020-02-25T21:03:03","slug":"what-to-do-when-your-date-and-time-are-incorrect","status":"publish","type":"post","link":"https:\/\/eshop.macsales.com\/blog\/58763-what-to-do-when-your-date-and-time-are-incorrect\/","title":{"rendered":"What to Do When Your Mac Tells You the Date and Time Are Incorrect"},"content":{"rendered":"\n
\"System
System Preferences > Date & Time shows that this Mac checks the current time and date against an Apple NTP server<\/figcaption><\/figure>\n\n\n\n

As a longtime tech writer, I’m sometimes asked how I get ideas for articles. Some of them come from readers who ask questions that intrigue me. The other day, an email arrived asking \u201cI have an iMac running 10.13.6 and somehow when I start my Mac it tells me that my date and time is incorrect, but it\u2019s not so I was wondering would you be able to explain to me in an easy way that I can understand: what\u2019s going on?\u201d<\/em><\/p>\n\n\n\n

Here’s what the problem is, along with a solution.<\/p>\n\n\n\n

Internal Clocks and NTP<\/h2>\n\n\n\n

The most likely culprit is a dead PRAM battery on the motherboard of an older Mac. Macs always check the time when they connect to the internet, through what\u2019s called an NTP (Network Time Protocol)<\/a> server. When the Mac is set up, you supply it with your time zone (and it can also determine your location through Wi-Fi positioning<\/a>), and it knows that the computer is currently at a certain offset from Coordinated Universal Time (UTC – the current time at the Prime Meridian in Greenwich, England). <\/p>\n\n\n\n

The screenshot at the top of this post shows that Macs are set to check the time through an Apple NTP server (time.apple.com).<\/p>\n\n\n\n

Older Macs used an internal battery (usually a CR-2032) to retain PRAM (parameter random access memory) settings and keep an internal clock running. If the Mac starts up and sees a discrepancy between the internal time and NTP time, you\u2019ll see an error message. It might appear that the date and time on the computer are correct, but even a slight discrepancy on the order of a few seconds causes the error message to be displayed.<\/p>\n\n\n\n

Which Macs Use Backup Batteries?<\/h2>\n\n\n\n
\"NWTCR2032_hero.jpg\"\/<\/figure><\/div>\n\n\n\n

The following Macs have CR-2032 or BR-2032 backup batteries (see image at right) that may need to be replaced from time to time:<\/p>\n\n\n\n