GT-I8262 cant unlock, missing samsung mobile usb port unlock SAM mobile USB port missing on device manager

pls chck this... the first is unlock but the 2nd not because no usb samsung mobile port driver, phone doesnt ask or install samsung mobile usb driver even an MTP driver, only digital camera sync popup. any on the settings adjustment, can u tell me where should i off that point. procedure: UART C3300k failed phone not found USB: *#7284# i choose modem on usb then i reboot the device and try to connect but still nothing.. no luck to get that point to be opened Z3x box phone not found the first 1 success unlock today 2nd cant unlock SAM mobile USB port missing on device manager