how to fix the compilation error

Arduino: 1.8.1 (Windows 10), Board: “Arduino/Genuino Uno”

C:\Users\ccc\Downloads\stepper_cus1\stepper_cus1.ino:10:26: fatal error: StepperMotor.h: No such file or directory

#include <StepperMotor.h>


compilation terminated.

exit status 1
Error compiling for board Arduino/Genuino Uno.

This report would have more information with
“Show verbose output during compilation”
option enabled in File → Preferences.

Wherever you got the StepperMotor.h name from should tell you how to get the library itself, which needs to be loaded.

Unfortunately there seem to be several libraries in existence with that name so which one was intended is anyone’s guess.