If the screen is off and won't turn on, make sure the battery has a charge. Plug in your device for 30 minutes before trying anything else. If it is on or if the battery has a charge you may need to "hard reset" the Nook. Although this is very uncommon, it may happen. Below are a few solutions that may help.
- Hold down the power button for 10-15 seconds. The Nook should power off and you can turn it back on again. Everything should work normally.
- If that does not work you will need to hold down the power button and the "N" button for 10 or more seconds. Again, this should force your device to power off and you can start it up normally.
- Take out the N2A Card and try the same steps again. Your Nook should boot up into Nook mode. You'll have to restart it again with the N2A Card in to boot up in Android mode.
One of the tasks above will usually correct this issue unless you have a hardware problem with the Nook. Our cards cannot cause hardware problems unless they are forcefully inserted wrong. If you determine you do have a hardware problem you will need to take the Nook back to the retailer if it is still under warranty. The Nook usually comes with a one-year (non-accidental) warranty through Barnes & Noble. Some retailers, like Best Buy, exchange them in the store under warranty.
Don't forget to hold onto your N2A Card until they return your Nook!
If you still have any kind of issue thenhttp://www.tablethelpline.com/nook-support/ you can take Nook Help
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