1. Create a new folder with an appropriate name on your computer.
2. Choose the correct download below for the computer system you are using, and save the download to the folder created in step 1.
3. Run the downloaded file to create the folder titled D7100Update, containing the following file: D7100_0101.bin
4. Format an approved memory card in the camera, then remove .
5. Copy the D7100_0101.bin file to the top level of the memory card using a memory card reader or similar device, do not copy the file into any folder on the memory card.
6. Insert memory card into the cameras memory card slot, and switch on.
7. Select Firmware Version from the setup menu and follow the instructions displayed to upgrade the camera's firmware.
8. DO NOT switch off the camera at any time during the update, doing so may result in the need for service.
9. After the upgrade is complete, turn the camera off and remove the memory card.
10. Check the cameras firmware version to be sure it completed.

Some users have reported using a card formatted in camera does not work, but that formatting a card in FAT32 using a computer before copying the update file to the card works.

Be sure to run the update file you downloaded to create the file named D7100_0101.bin and only copy that file to the root of the SD card. Copying the downloaded file itself will not work.

At no point in the process should the camera be connected to anything else via the USB or any other ports on the camera. If you try to copy the .bin file to the card while it is inserted in the camera and the camera is connected to the computer via USB, it won't work.

If the camera is attached to a battery grip, remove the grip and use a single battery in the camera. I would even go so far as to disconnect any flash attached to the camera.

Be sure to turn off the camera each time before you remove or insert the memory card in the camera. Also be sure to 'eject' the memory card (via software) on your computer before removing it from the reader.