The default installation of SAMBA will be set to use “user-level security” which means that each time a Windows machine wants to access data on the Ubuntu smb share it must supply a username and a password. However, the SAMBA password is not the same password as your normal Ubuntu password. Instead, you must explicitly set a special SMB password which is associated with your normal Ubuntu username/password.
Assuming that your normal ubuntu username is “ubuntu_user”; to set a SMB password for your Ubuntu user account you need to start a terminal and then type these commands; first you run
“sudo -i”, then you run
“smbpasswd ubuntu_user” and then you enter a brand new SMB password (you need to enter it twice to confirm it)