Recreate BUILTIN\Administrators - SQL Server 2005

If you have deleted the BUILTIN\Administrators account you can use the following TSQL to recreate the account again.

n.b. You will need to be a member of sysadmin to grant the permissions.

USE master
go
EXEC sp_grantlogin 'BUILTIN\Administrators'
go
EXEC sp_defaultdb 'BUILTIN\Administrators', 'master'
go
EXEC sp_defaultlanguage 'BUILTIN\Administrators', 'us_english'
go
EXEC sp_addsrvrolemember 'BUILTIN\Administrators', 'sysadmin'
go

Related Articles:

1.) How to make unwanted access to SQL Server 2005 by an operating system administrator more difficult

http://support.microsoft.com/kb/932881 

2.) Error 15401: Windows NT user or group '%s' not found. Check the name again. 
http://support.microsoft.com/default.aspx?scid=kb;en-us;324321