UnicodeDecodeError: 'utf-8' codec can't decode byte 0xa7 in position 3: invalid start byte

I see. Basically, if I want a quick go around, I can just mimic the OS system encoding setting that matches the file. But even if it can open the file, Blender still won’t recognize those characters. So in the long run I still have to change the files(both .obj and .mtl) to utf-8?