Right now, if you plug the camera into a USB port on a computer device (PC, cell phone, tablet, anything that can read and play files), the camera defaults to "MASS STORAGE" mode and disables all access via the camera's interface other than turning the camera off by holding down the Power button. All you can do is view the files via the connected device.
I'd like to suggest a feature where holding down the Menu button (or whatever button is easier to program) on the camera switches the camera back to recording mode, so you can access the menu and make changes, let's say to view and edit settings after a firmware upgrade, or just confirm the upgrade was successful. You can then reconnect the camera or hold the Menu button down again to switch back to Mass Storage mode.
I had a heck of a time yesterday upgrading our two recently purchased A119S V2's from V1.7 to V2.1
You simply CANNOT do it as the instructions says.
I have NO "powered" USB ports on any of my two Laptops, as required. I have one "powered" USB 2.0 port on my Dell Desktop which did noting different. I tried ALL 10+ USB (3.0 & 2.0) on all three computers like instructed and all I saw on VIOFO Dash Cam screen was "MASS STORAGE".
I use 64GB SD Cards in my Cams while driving. Each Cam came with a "free" 16GB SD. I removed them and saved them. I use the 16GB SD's for updating firmware. I formatted to FAT32 and then using desktop Computer, I downloaded V2.1 and then moved it onto the 16GB SD with my card reader, and placed that SD Card in Cam. I used an iPhone power supply, plugged VIOFO cable into that and turned on cam, while on my kitchen counter. I selected FIRMWARE UPDATE and presses "enter". In a few seconds red light blinked and Cam Firmware was updated. I shut off, removed 16GB SD and replaced with 64GB SD card and powered up cam. Then (while on kitchen counter and still pluged in) I made ALL Settings. I took Cam out into vehicle...........Perfect !!