For some reason my physical vista computer can connect to file sharing of the Vista Guest but the Guest cannot connect to the physical vista. Networking is configured as Bridged. Firewalls are off. One Guest also cannot connect to another Guest. Probably the same reason. OSX can connect to the physical vista.
can connect They can connect if you add the login information to your profile manually. if you attempt to connect to a share without a username/pass then instead of prompting for a login, you get the failure code. Also, for some reason OSX doesn't automatically see the guest os in the network without manually targeting it's IP.