Because you didn't add:
Now go back into Nautilus as gksu and check on the "Guest Access" box in Sharing Options for /media/Shared.
Guest access is greyed out and unticked.
To the global section of smb.conf and restart samba
usershare allow guests = yes
It's asking you for a password because that's the way you set up the share:
When I do the same from the Dell I see just print$ and shared (lower case 's'). I double click on shared and am asked to enter the password but I can't get in, it just returns to the password window.
See  above.
\\HPDC7700 HPdc7700 server (Samba, Ubuntu)
sudo net usershare info
[sudo] password for roy:
That may be the greatest error message in the history of computers and software. It not only tells you the nauture of the problem but it tells you exactly how to fix it:
I just tried to share an NTFS folder though using Properties, Share but get this message:
'net usershare' returned error 255: net usershare add: cannot share path /media/Video_XP as we are restricted to only sharing directories we own.
Ask the administrator to add the line "usershare owner only = false"
to the [global] section of the smb.conf to allow this.
Open up the smb.conf on the Dell and add the following line to the [global] section of smb.conf:
Then restart samba
usershare owner only = false