I figured it out.
The particular Microsoft Account aka Microsoft ID aka Windows Live ID is based on an email address email@example.com which has "Firstname Lastname" as the user name.
The password is that of the the online Microsoft Account but the username for connecting to shares is the first name of the Microsoft Account, in this case Firstname.
A good clue is that C:\Users\Firstname is the home directory.
- USERNAME = first name of username in Microsoft Account = folder
name under C:\Users
- WORKGROUP = whatever group the machine is in
- PASSWORD = password used to login to the Microsoft Account on the
I have confirmed this works with connections from:
- Ubuntu 12.10
- Ubuntu 10.04LTS
- Mac OS X 10.8.2
From other Windows 8 and 7 machines the username is the full email address: firstname.lastname@example.org