1. Insert your SDCard.
  2. Startup your Win32DiskImager.
  3. On the Image file field, specify the desired filename of the image.
  4. On the Device field, select the drive letter of the inserted SDCard.
  5. Click the Read button and wait until it's done.
  6. Once completed, click the OK button.
  7. Click the Exit button.

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Writing an Image File to an SDCard using Win32DiskImager