I have had no luck in the past with upgrading the firmware for my XC 50-230 mm on the XT-3. Today, I found there was a new version of the lens firmware available from Fuji, so I hopefully downloaded the file and tried to update the firmware on my XT-4. The same thing happened as in the past. Even though I have put the file on the card in slot 1, the camera reports there is no firmware on the card. Since I had just updated the firmware for my 10-24 mm lens following the exact same recommended procedure I conclude there is either something wrong with the downloaded Fuji file or there is something unusual about this lens. Does any one have a solution to this? It's no big deal. I only use this lens as a lightweight zoom when travelling, and it works very well.