I have recently completed the migration of my exchange 2000 server to an exchange 2007 server installed on Server 2008 in a mixed 2000/2008 environment. The Exchange 2000 server was experiencing severe mechanical problems, and I was able to get all the migration steps done and test the e-mail system before it failed completely. I was able to remove the exchange server 2000 installation according to instructions, moved every store and feature to the new server, and removed the connectors, leaving the 2007 as the only exchange server installation in my organization. While I was beginning to run DCPROMO on the old 2000 domain controller, it failed catastrophically.DCPromo didn't start, so I know that it was not corrupt or in the middle of demotion.I removed the old server from the domain using server 2008's active directory tools, deleted the server from the domain controllers window, checked the box that states the server is permanently offline, and this went through without problems. Again, DHCP, DNS, all the domain services I can see are working correctly.I can access all features of the network, the services are all functioning. But on the failure of the old domain controller / exchange server, now my outlook 2000 clients are all terribly slow to open. I can open them, then in about 1 minute I get a message that the server didn't respond in a timely manner. I click retry, and between 2 and 5 minutes later outlook connects.I have already made sure that DNS and address resolution is working properly. If I go into the mail properties in control panel, and usi the check names applet to see if a name is resolved, it occurs almost instantly. Ping response is good, almost no latency, to either the IP address or the DNS name.And once the client opens, it is not slow to respond. It just takes forever and a timeout or two to connect.Any suggestions?ThanksChris Nogy

Well as you may have realized by now, Exchange 2007 does not work with Windows 2000 DCs. If they exist, you must hardcode the 2003 sp1 DCs into Exchange 2007. As for Outlook 2000 being slow, EEK! why do you still have Outlook 2000? Outlook 2000 is not supported with Exchange 2007. You need Outlook XP (2002) or later. "Note: Outlook 2000 isn't supported by Exchange 2007" http://support.microsoft.com/kb/555851

Hi, Base on KB 555851,We recommend you to upgrade your outlook 2000 to Outlook 2007. Besides, please ensure that the DC is in health state. You can run DCdiag /v from a command prompt to check it. Dcdiag Overview http://technet2.microsoft.com/WindowsServer/en/library/f7396ad6-0baa-4e66-8d18-17f83c5e4e6c1033.mspx?mfr=true Also please ensure that all the DCs are in the same state, please try to use Replication Diagnostics Tool to check it. Example 10: Showing the replication status of a forest using replsummary and wildcard characters. http://technet.microsoft.com/en-us/library/cc773062.aspx Hope it helps. Xiu