Microsoft says In an effort to provide customers with more secure products, Microsoft Windows Server "Longhorn" and Microsoft Windows Vista will only support the follow on release to SQL Server 2005 Service Pack 1 (SP1) or later. Earlier versions of SQL Server, including SQL Server 2000 (all editions including Desktop Engine edition, a.k.a MSDE), SQL Server 7.0, and SQL Server 6.5, will not be supported on Windows Server "Longhorn" or Windows Vista.

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