The handsets have a problem in their software that will cause them to lose access to their central functions if they don't receive a critical update.
If the new version of the operating system is not installed before 3 November, they will be cut off from internet browsing, email and the App Store. Over-the-air software updates will also stop working, meaning users will be forced to back up and restore with a PC or Mac.
The problems arise from a software issue which means the phone will no longer be able to rely on its GPS location and will stop having the correct time and date. Since all of those features use that time feature, they will be unable to work after the cut off.
The iPhone 5 can be easily updated by heading to the Settings app, clicking the option for general, and pressing software update. If the phone still needs to be updated, a reminder should appear and the new software can be downloaded.
The iPhone 5 must be updated to iOS 10.3.4 if it is to avoid being affected by the problem.
iOS 10.3.4 is far from the latest version of Apple's operating system, which is currently on iOS 13. But it is the newest update that works on the iPhone 5.
The issue arose from a GPS time rollover problem that affects a variety of GPS-enabled devices. It started causing problems from April this year, but will not affect iPhones until the deadline arrives.
It will start to hit iPhones and iPads just before 12am UTC on 3 November.
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