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Note: Note: SQL Server 2008 Express includes both 32-bit and 64-bit versions. SQLEXPR32_x86 is a smaller package that can be used to install SQL Server 2008 Express onto only 32-bit operating systems. SQLEXPR_x86 is the same product but supports installation onto both 32-bit and 64-bit (WoW) operating systems. SQLEXPR_x64 is a native 64-bit SQL Server 2008 Express and supports installation onto only 64-bit operating systems. There is no other difference between these packages.