Yeah I know the thread is old. I'm using the latest 6.3.5, but as it looked like a Windows related problem I figured it didn't make much of a difference.
After hours of getting the private folders to work, it suddenly just happened. In the beginning, cmd and "net use" didn't show me anything but all of a sudden it did and things started working after a "net use * /del".
Now I just hate that I don't know what made the difference but at least it works.