Why the 'Protocol Error' is raised when i try to build virtual enviroment with pyvenv?

Question

My host machine is win8 and virtual machine is Ubuntu 16. I make a dir--web_django in the Ubuntu as the synced folder. When I try to use pyvenv create a virtual environment, the error is raised:

Error: [Errno 71] Protocol error: 'lib' -> '/home/ubuntu/web_django/web/lib64'

So, why the error is raised?

I guess that the reason is i set the dir, web_django, to be the synced folder in vagrant file. But i use virtualwrapper successfully in the web_django.