I have tried installing this (from scratch) now several times, and every time it fails in the same spot during the install. It gets to installing the Hub Transport Role, and bombs with:Summary: 9 item(s). 5 succeeded, 1 failed.Elapsed time: 00:29:02Organization PreparationCompleted Elapsed Time: 00:03:02Preparing SetupCompleted Elapsed Time: 00:00:00Copy Exchange FilesCompleted Elapsed Time: 00:06:03Language PacksCompleted Elapsed Time: 00:00:04Management ToolsCompleted Elapsed Time: 00:00:06Hub Transport RoleFailed Error:The execution of: "$error.Clear(); if ($RoleStartTransportService) { start-SetupService -ServiceName MSExchangeTransport }", generated the following error: "Service 'MSExchangeTransport' failed to reach status 'Running' on this server.". Service 'MSExchangeTransport' failed to reach status 'Running' on this server. Elapsed Time: 00:19:44 Client Access RoleCancelledMailbox RoleCancelledFinalizing SetupCancelled========================================It looks like the transport service will not start. I get this in the event logs when it fails:(PID 1836, Thread 39) Task start-SetupService writing error when processing record of index 0. Error: Microsoft.Exchange.Configuration.Tasks.ServiceDidNotReachStatusException: Service 'MSExchangeTransport' failed to reach status 'Running' on this server.There are other events leading up to this...mostly about LDAP. For the purposes of testing 2010 beta, I am installing Exchange on the domain controller (which was setup clean with a new domain, solely for this purpose). The DC is Windows 2008 Standard, 64-bit. Exchange's setup/preinstall checks everything out and everything came back as OK for clean install.Any ideas what is wrong? Or what other data you might need to help me out?

Have you disabled/untick IPv6 in Local Area Connection? In that case you need to disable it properly with registry setting as per below article... Exchange 2010: Hub Transport Role Installation Fails http://exchangeshare.wordpress.com/2009/04/18/exchange-2010-hub-transport-role-installation-fails/Amit Tank | MVP Exchange Server | MCITP: EMA, MCSA: M | http://ExchangeShare.WordPress.com

hi,look at here, it was posted before ;http://social.technet.microsoft.com/Forums/en-US/exchange2010/thread/8f6ff508-2c09-4140-ba14-eca32bc5bf1dregards,Mumin CICEK | Exchange - MVP | www.cozumpark.com | www.mumincicek.com

Thanks. Turning IPv6 back on fixed it.I assume this bugwill be fixed for the RC for 2010? Or is it more considered a bug in Windows Server 2008?

Thanks. Turning IPv6 back on fixed it.I assume this bugwill be fixed for the RC for 2010? Or is it more considered a bug in Windows Server 2008? I guess it is Windows 2008, not Exchange. It is coming in Exchange 2007 also... :)Amit Tank | MVP Exchange Server | MCITP: EMA, MCSA: M | http://ExchangeShare.WordPress.com