Microsoft will end support for Windows Server 2003 in July, 2015. What does this mean to you? It comes down to this: there will be no new patches or security updates, which puts your business at risk. With Microsoft estimating that it takes 200 days to migrate your applications, the time is now to start your move. It is foolish to keep using an outdated and at-risk operating system in your business environment.
You can either move to Windows Server 2008 R2, which also has issues, or to the newest available server operating system, Windows Server 2012 R2. You can find more information here.