如何阻止Windows Server 2008进入睡眠状态？

I have just upgraded my server 2003 to serrver 2008. As I write this, my site is available externally. If I were to try again in the morning,the site won't come up. However, if I log back onto the server or access the website from another computer on the network, it works just fine...again!I have just upgraded my server 2003 to serrver