That's odd. No update.log file in the HWID folder would mean that the SD card flash didn't even start properly.

I don't recall seeing that almost three year old thread previously and lazily i didn't look very far back before. Butters suspected flash damage to that Nav VI and i agree with that diagnosis after reading the symptoms reported by gigidel. There are two quite different basic causes of "System Software Missing" message. Broadly speaking, those are software (benign) and hardware (serious):

If the device can't start only because the main system software (firmware) in region 14 is either missing, corrupt or not able to interact with the device's bootloader/x-loader then that's usually very easily correctable by just flashing the correct healthy firmware to it. Such a device showing "System Software Missing" always defaults to preboot mode and re-flashes easily via Updater or WU. In your case, that may indeed have been the problem seeing you don't have the update.log file on the card, or as i said previously the device may have simply needed a second boot cycle.

However a device with a failing flash chip where the physical damage involves region 14 cannot be repaired by software means so it's usually fatal. Unfortunately, although gigidel's device did default to preboot, or could attain it manually, flashing attempts with WU & Updader.exe failed. It also didn't take a flash from a media card. Not economically repairable because it needs the chip replaced with reballing and then reprogramming with special equipment not readily available outside Garmin.