Am having a problem with my tecno f8 mt6589 chip, the phone got bricked, hard bricked, i got a back up from someone using a similar phone and tried flashing back using ur guide in this forum. i have never successfully flashed the new rom cuz i keep getting a "s_da_sdmmc write failed (3149)" error. i installed the mtk drivers on my laptop which is a win 8.1 OS and when the phone is plugged into the laptop wit a usb, a mtk usb vcom pops up in device manager, i never get the mtk usb preloader, i donno if thats the problem.. but pls can u help?