Welcome to the HP Support Community. This is a great place to get support, find answers and tips to your technical queries. I have reviewed your post and I understand you have questions about your HP Sprocket.
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If the paper is loaded with a micro-SD card with available storage - Captures a photo using the camera, a shutter sound plays, saves a digital version to micro-SD card, and one copy of the photo prints
If no paper is loaded with a micro-SD card with available storage - Captures a photo using the camera, an error sound plays, and saves a digital version to the micro-SD card (Micro-SD Storage LED blinks red)
Installing a Micro-SD card -
1) Make sure your HP Sprocket 2-in-1 is powered OFF. Use a fingernail to insert a micro-SD card into your device. The label on the micro-SD card should be facing up towards the Paper Cover.
2) The Micro-SD Storage LED will turn red if there is a card error. Remove the micro-SD card, restart the printer, and then reinsert the micro-SD card to clear the error.
3) When a micro-SD card is inserted in the device and the device is connected to a computer using the USB Charging Cable, instant camera and printer functionality is unavailable.
Hope this helps!
Let me know how that goes.
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