Hello I am now also having this problem.. I have had my Viofo A119S for nearly 18 months and it works perfectly..I have carried out numerous firmware updates from the Viofo support site successfully copying the bin files to my SD card then inserting into the camera and plugging into wall socket and turning camera on it updates firmwares easily. I then reset everything on camera once firmware updated and away to go..... I am currently of the A119S 2.61 firmware dated 180730...this has worked fine but I have seen there is a newer version 4.0 available..
I am very familiar with the upload processes but I have spent nearly 2 hours trying to update to V 4.0 with no success. I have used 3 different 32GB SD cards.. (I unbranded, 1 Lexar 633x microSHC1 and a Samsung 32GB Pro Endurance these have had no problems previously updating firmware versions) I have formatted these cards on my computer and also in the camera, I have downloaded the Bin file to the card on the computer and inserted it in the camera before powering up via computer (fail) and tried powering up via wall charger (fail) when trying to power up camera via computer camera just says in Micro SD reader mode and nothing else happens. I have tried downloading the bin file to the SD card whilst it is in my camera which it did but again it fails to update.. Every time I try the update when the SD card is in the camera and powering up from wall socket all that happens is the Viofo log on comes up and the camera begins automatically recording (red light only flashes).. (This seems to be the same problem as another members post).. I do find these problems very strange as I have updated firmware on this camera many times over the last year or more with no issues whatsoever??? Please can anyone offer some suggestions.. Thanks again everyone.....