I need some help on understanding the differences between Windows and SQL Server Authentication:
We have a SQL Server 2008 set to SQL Server and Windows Authentication Mode.
There is one A/D user -- munis -- that can log into our SQL Server. That user also has a login in SQL Server with Public and Sysadmin roles.
There is another user -- cnorton -- who cannot log into the SQL Server and has no local login in the SQL Server.
I thought that Windows authentication allowed A/D (domain) users to log into a SQL Server. User cnorton has more A/D privileges than does user munis, like Domain Admin and Sysadmin.
So my question is does Windows and SQL Server Authentication mode require a local SQL Server login, and why?