Topic: "Authentication is required" problem with dual boot
After a fresh-install of #! 20101205, I couldn't access my XP partition any longer (/dev/sda1, 16GB). When I opened nautilus and clicked on the XP partition in the side-pane, I would get a pop-up saying "Cannot mount 16GB file system. Authentication is required".
After numerous head-banging with fstab, mount, etc., the solution turned out to be installing disk-manager. I ran disk-manager as root, checked "enable write support" in "NTFS policy", and configured the XP partition under "status". Voila! Works like a charm.
Posting this because I have seen variations of the same question in many forums, but no definitive solution.
