With Windows Server 2003, Microsoft successfully broke ties to some of its older application programs. In some cases, Microsoft decided not to support a program under Windows Server 2003.
For example, Windows Server 2003 doesn't support Exchange 2000, due to the number of significant changes made in Internet Information Services (IIS) 6, which Exchange heavily relies on. But Exchange 2000 isn't the only application left behind.
Windows Server 2003 doesn't support the following applications. If you're running any of these applications, you'll need to consider your options.
Organizations can either migrate to Exchange 2003, which both Windows 2000 and Windows Server 2003 support (although full functionality requires Windows Server 2003), or they can investigate alternatives, such as GroupWise or SuSE Openexchange Server.
Companies can either upgrade to SQL Server 2000 Service Pack 3 or later, wait for the next version of SQL Server before migrating to Windows Server 2003, or consider alternatives, such as Oracle or PostgreSQL.
Organizations can either install Content Management Server 2001 Service Pack 2, or they can upgrade to Content Management Server 2002.
Companies can either install Internet Security and Acceleration Server 2000 Service Pack 1 or later plus the required updates for Internet Security and Acceleration Server 2000 and Windows Server 2003 (which you can download from Microsoft's Web site), or they can wait for Internet Security and Acceleration Server 2004, which Microsoft released the beta version for this year.
Exchange and SQL are the most affected applications; older versions simply won't work under Windows Server 2003. Other applications such as Content Management Server and Internet Security and Acceleration Server work, but they require new service packs.