I'm in the process of upgrading our AD Controllers to Server 2008 R2 and have successfully introduced a 2008 R2 server into our AD environment as a secondary. Everything seems to be working great and I'll transfer the FSMO roles soon. However, I did notice a number of client machines pointing to the old Server 2003 secondary which I have shutdown for the moment. I've modified the SRV records and changed the priority for that old controller so that it won't be referenced but the strange thing is even after rebooting a client machine it still wants to authenticate against it? When I look at the SET environment variable LOGONSERVER it's still pointing to the old secondary as it's logon server. What I need to do to have the clients use the existing primary or the new secondary?? Thanks.

plesae post the ipconfig /all from the clienthttp://www.virmansec.com/blogs/skhairuddin

Why you shutdown your 2003 DC? Please make sure that the online DCs are given lower priority on SRV records. Your client computers are able to logon? Even with lower SRV records, if you run echo %logonserver% on your client computers, it give the old DC name? For upgrade to AD DS 2008 / 2008 R2, refer to this Microsoft article. If you want to delete your old DC, I recommand to you to demote it and not keeping it offline. If you want to keep offline your 2003 DC, I think it will be better to delete its A and SRV records (Once online again, you can run ipconfig /registersdns and nltest /dsregdns) but I don't agree with you for keeping it offline. This posting is provided "AS IS" with no warranties or guarantees , and confers no rights. Microsoft Student Partner Microsoft Certified Professional Microsoft Certified Systems Administrator: Security Microsoft Certified Systems Engineer: Security Microsoft Certified Technology Specialist: Windows Server 2008 Active Directory, Configuration Microsoft Certified Technology Specialist: Windows Server 2008 Network Infrastructure, Configuration