Another fix:
Change Tools->Processor->Atmega 328P to Atmega 328P (Old Bootloader).
This worked for my Arduino Nano with CH340, using Arduino IDE 1.8.5 under Linux Ubuntu 17.10.
Another fix:
Change Tools->Processor->Atmega 328P to Atmega 328P (Old Bootloader).
This worked for my Arduino Nano with CH340, using Arduino IDE 1.8.5 under Linux Ubuntu 17.10.