I've looked at other questions on this topic, but I haven't found anything that corresponds to my experience trying to actually do this. I want to SMB mount my Win7 VirtualBox guest disk on my Ubuntu host.
In the VM (that is, the Windows 7 guest), I've shared the folder, I think. I did that by going to the control panel, opening the 'Share With -> Advanced Settings' dialog, and making the disk shared. From the Ubuntu host in Nautilus or Thunar, I can see the VM (which calls itself "VM7").
When I try to access the share from Nautilus or Thunar, I'm presented with a username/password verification dialog. If I give the username and password that lets me use the Windows guest, it doesn't work; the dialog just pops up again.
This seems like something that should be pretty simple. What am I doing wrong?
edit oh also, from the Windows (guest) side, the C: "disk" is shared with no password protection: "People without a user account and password for this computer can access folders shared with everyone."