Error while running sim_vehicle.py OSError: [Errno 90] Directory not empty:

After following all the steps from http://ardupilot.org/dev/docs/sitl-native-on-windows.html
I ran sim vehicle.py using the following command : python sim_vehicle.py -j4 --map --console -v ArduCopter
and it it giving the above error
But when I go to the particular directory it is empty.
Anybody facing a similar issue?
Any solution to this particular problem?