Thanks, Now it's working.
Thank you Vary much.

This was the error when I clicked fast prevew

Traceback (most recent call last):
File "C:\Program Files (x86)\Blender Foundation\blend4web_ce\blend4web_ce\addons\blend4web\server.py", line 332, in execute
os.mkdir(tmpdir)
PermissionError: [WinError 5] Access is denied: 'C:\\Program Files (x86)\\Blender Foundation\\blend4web_ce\\blend4web_ce\\tmp'

location: <unknown location>:-1