Hello, I am installing Windows NT Server as a Backup Domain Controller of a Windows 2000 Server. When it comes-up at screen where it asks about Domain name (where this server will participate as a Bacup server), administrator name and password, when I provide all information and press next it gives me an Error that "The machine account for this computer either does not exist or is inaccessible" Now when I creat an account for this Computer in Windows 2000 Domain Controler and then I proceed installation in Backup Server (WindowsNT machine) then it again gives an Error that "The Computer name is already configured as a Workstation or Server on the domain. Please contact your domain administrator" Now please write me the steps thats I follow to configure my Backup controler for Win2000 server. Please help to solve this problem I will really be thankful to you. Farhan

If your W2k DOMAIN Server was installed by itself, and the mode was changed from MIXED to NATIVE, I don't think you're going to be able to install a NT4 BDC into that Domain. Come to think about it, even an upgrade from NT4 server to W2k server is supposed to be done on the PDC. Its so that the W2k Domain server ends up with the PDC FSMO role. I'm pretty sure you'll have to install that NT4 Server as a member server. Remember, W2k did away with the NT4 type PDC/BDC servers, each W2k Domain server is now a peer.