Kindle e-reader owners have to do this...

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Kindle e-reader owners are facing a deadline to update their devices or lose internet service.

Amazon is warning owners who bought Kindles in 2012 or before that they must install a crucial update before Tuesday, March 22 or lose internet connection. That means you won't be able to download books or access the Kindle store.

If you miss the deadline, you will have to download the update on a computer or laptop, then plug in your Kindle via a USB to transfer the software to the device.

Amazon has posted directions for how to download the update.