(Then, Enter download mode your Samsung Galaxy A5
TThe first method that can be applied is the hardware one.
So, first of all, turn off your phone: press power key and choose “reboot system” or keep pressing power button for a few seconds.
When done, press power, volume down and home buttons at the same time, for a few seconds – until the Android logo is being displayed on your Samsung Galaxy A5.
You can then connect your Smartphone with your computer for resuming the update operation.)