When you install Microsoft SQL Server 2005, you may receive the following error message:
SQL Server Setup failed to execute a command for server configuration. The error was [Microsoft][SQL Native Client][SQL Server]Cannot alter the login 'sa', because it does not exist or you do not have permission.. Refer to the server error logs and Setup logs for detailed error information.
This problem occurs because you tried to install SQL Server 2005 on a domain computer that has a Windows group or a user who has one of the following names:
The Setup program cannot call the sp_SetAutoSAPasswordAndDisable stored procedure to disable the sa login when Windows Authentication mode is selected.
To work around this problem, select the Mixed Mode (Windows Authentication and SQL Server Authentication) option when you install SQL Server 2005.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
Microsoft SQL Server 2005 Standard Edition, Microsoft SQL Server 2005 Developer Edition, Microsoft SQL Server 2005 Enterprise Edition, Microsoft SQL Server 2005 Express Edition, Microsoft SQL Server 2005 Express Edition with Advanced Services, Microsoft SQL Server 2005 Workgroup Edition