It's used on Vista (and I think Server 2008) to add in an administrative user as, by default, the builtin\admins are no longer automatically sysadmin on those OSs. It's only used with SQL 2005 SP2 and SP3
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability
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