You can upgrade instances of SQL Server 2000 or SQL Server 2005 to SQL Server 2008. Before running SQL Server Setup to upgrade to SQL Server 2008, review the following topics about the upgrade process.
Planning a SQL Server Installation
Documents installation requirements, system configuration checks run by SQL Server Setup, and security considerations for a SQL Server installation.
Version and Edition Upgrades
Documents supported upgrade paths to SQL Server 2008.
Using Upgrade Advisor to Prepare for Upgrades
Describes Upgrade Advisor, a tool that analyzes instances of SQL Server 2000 and SQL Server 2005 to identify known upgrade issues.
Upgrade How-to Topics
Provides links to procedural topics for upgrading to SQL Server 2008.
Backward Compatibility
Lists the significant changes that might affect your applications after you upgrade to SQL Server 2008.