You are the administrator of a Windows 2000 network.  Your network includes 50 Windows 98 computers. You are adding 40 new PXE compliant computers to the network. The hardware on each new computer is configured identically. You are using a Remote Installation Services (RIS) image to deploy Windows 2000 Professional to the 40 computers. You successfully install Windows 2000 Professional on the first 10 computers. However, you cannot install Windows 2000 Professional on the remaining 30 computers. You want to install Windows 2000 Professional on the remaining 30 computers. What network component do you need to change?