The camera only shows the "Update" button if it detects the correct file on the root of the SD card. Ensure the file is not inside a folder named "DCIM." The "CHA" Error
If the camera turns on, focuses, and writes to the SD card, you are good to go. Spend less time worrying about software versions and more time enjoying that distinct 2005 CCD rendering. nikon d50 firmware
Unlike Canon’s CHDK or Nikon’s later “hacked” firmwares (e.g., Nikon Hacker for D90/D3/D700), the D50 never received any community firmware modifications. What you see is what Nikon shipped. The camera only shows the "Update" button if