Some sage advice: No matter what someone tells you, do not—under any circumstances—change the date on your iOS device to Jan. 1, 1970.

It sounds weird, but there’s good reason: it will render your device unusable.

As 9to5Mac reported, Reddit users have discovered setting their Apple devices’ date back 46 years will result in a “bricked” device. According to Reddit users, the bug seems to only impact iOS using Apple’s newer 64-bit processors running iOS 8 and up. Devices equipped with a 64-bit processor include the iPhone 5S or newer, iPad Mini 2 or newer, and iPad Air or newer, along with the iPad Pro.

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A video posted by Apple news site Macworld shows the bizarre bug in action. After setting the date to Jan. 1 1970, senior editor Roman Loyola restarts an iPad Mini 4, and despite the normal Apple logo showing up as the device powers on, that’s as far as it gets. Throughout the three-minute video, the Apple logo flashes periodically on the iPad’s screen, as if the device is trying to finish starting up, but nothing happens. Users are unable to fix the device by connecting it to a computer and trying to restore it through iTunes.

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Nearly a full day later, Loyola was still waiting for the iPad Mini’s battery to run out of power to see if the device fixes itself. Some users have reported that the impacted device will restart and resume working after the battery completely drains, but that it operates slowly until the date is corrected. Other comments on Reddit indicate a trip to the Apple Store is the only fix.

Apple declined to comment. Thus far, no other dates have been found to have the same effect on iOS devices.

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The 1970s bug (for lack of a better name) is reminiscent of another random problem that impacted iPhone users last year. A text containing a combination of Chinese and Arabic letters could crash another user’s iPhone. Upon receipt of a message, the iPhone would power off and then back on. The message’s contents was not something anyone would normally receive, but once the trick was known, people started abusing it.

How anyone was able to discover that a particular string of text could force and iOS device to restart is just as mind boggling as to why anyone would want to set the date on an iOS device to Jan. 1, 1970.