Arduino couldn't upload the program

I am using arduino uno board and trying to upload it with a serial communication code but nothing is writing to the arduino board.
And I am getting an error as
"avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x15
Problem uploading to board. See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions."

Hope anyone could come up with a solution

That message usually means that the Arduino IDE cannot find your Arduino board, or perhaps that you have selected the wrong type of board.

What Arduino board are you using?
What version of the Arduino IDE?
What PC operating system?

What happened when you tried the Troubleshooting guide?

Have you been able to upload the example Blink program?

...R

See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.

So, why didn't you?

Thank you for your reply sir,
The board I am using is Arduino UNO R3
Arduino Software Version 1.8.5
Windows OS
Troubleshooting guide suggested to check the selected board and the serial port, installation of drivers, access to the ports, physical connections, auto-reset and bootloader. I had tried all and there are no issues.
Now as I am uploading, error is "Problem uploading to board"
I have checked only with serial communication program. Now I will try with Blink program.