The following knowledge base article describes the known issues when you install Microsoft SQL Server on a computer that is running Windows 7 or Windows Server 2008 R2 .
List of known issues when you install SQL Server on Windows 7 or on Windows Server 2008 R2
For all editions except express edition of SQL Server 2008 running on Windows 7 and on Windows Server 2008 R2, you must have at least SQL Server 2008 Service Pack 1 (SP1) installed. Express edition already includes Service Pack 1.
For all editions of SQL Server 2005 running on Windows 7 and on Windows Server 2008 R2 , you must have at least SQL Server 2005 Service Pack 3 (SP3) installed.