Whatever the sound I chose to change any event sound to, it will revert back (as you can see from 2 attached pictures)
I also tried to change the installed folder from “Program Files (x86)” to another folder but it did not work.
Please kindly help… 
Thank you,
Bright
Hi - this may sound like a stupid question, but which application are you referring to. I do not recognize the screenshots.
It’s MT4 and I just know that I need to enter not just click away.
Thank you very much sir!
from my first day of trading i have been using MT4 that is really comfortable.
I had the same issue a few time ago.
The only way you can change the default alert sound in MT4/MT5 is by replacing the ‘alert.wav’ file.
You’ve probably replaced that file in a wrong directory. Instead of trying to find the right directory manually, navigate to the ‘Events’ tab in Options, double click on ‘alert.wav’ next to ‘Alert’ and select ‘Choose other…’:
That’ll bring you to the right folder where you can replace the alert sound file. Make sure the extension of your custom sound is .wav, otherwise it won’t work.