A. Windows Server 2008 introduced the new Server Manager management interface, which focuses management around each role and feature. Server Manager in Server 2008 isn't remotable, however, so you can't use it to remotely manage any platform. The Remote Server Administration Tools don't install on Server 2003, so you can't use Server Manager to manage Server 2003.
Server 2008 R2 introduced a remotable Server Manager, but only Server 2008 R2 contains the services to support a remote Server Manager connection. So even with the 2008 R2 version of Server Manager, you can't manage a Server 2003 box.
This limitation doesn't stop you from running some of the individual MMC snap-ins on the Server 2008 and Server 2008 R2 platform and remotely managing 2003 boxes, but this won't work for all snap-ins.
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