I created one file .exe with auto-py-to-exe and added .ico file. When the file was in output folder the .ico was working as intended and my custom icon was there but every time when I copy this file into another folder it changes back to default python icon. What I am doing wrong?
Try this line, it will make your .exe in one file with icon you set and it will be windowed.
pyinstaller.exe --onefile --icon=myicon.ico --windowed app.py