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Nikon D7100 Troubleshooting
This troubleshooting page will help diagnose problems with the Nikon D7100
“The green light on the back of the camera flashes and the rest of the device does not appear to power on.”
The “Green Light of Death” occurs in many Nikon cameras. A good forum post explaining several solutions can be read about here.
Remove the battery and let sit for about 5 minutes or more.
“The camera will not focus or focuses slowly.”
If the camera is back focusing or not focusing on the intended object, the auto focus setting might be turned off. Adjust the auto focus using this guide.
If the previous guide does not fix the problem other settings may be altered. To reset the camera to its factory settings, use this guide.
“SD card not properly functioning”
Nikon D7100 not recognizing when a SD card is inserted. To fix this issue remove the battery and SD card. Then turn and hold the power knob to the light bulb position for 15-30 seconds. Finally reinstall the SD card and battery and turn the camera back on.