With my TAP customers, we got MSFT involved (support for the upgrade is provided for TAP members). For my internal systems - I exported the mailboxes and reimported them on a fresh server. I never could make the upgrades work. From: exchangelist-bounce@xxxxxxxxxxxxx [mailto:exchangelist-bounce@xxxxxxxxxxxxx] On Behalf Of ExchangeMailingList Sent: Saturday, November 14, 2009 4:27 PM Cc: exchangelist@xxxxxxxxxxxxx Subject: [ExchangeList] 2010 RC to RTM Upgrade Has anyone successfully upgraded?? My attempt fails by telling me that the HUB transport role is not installed, (It is although it does give an error now in the GUI, worked fine til the upgrade attempt). I also get these [11/14/2009 20:58:33.0478] [1] [ERROR] The Mailbox server role is not installed on this computer. [11/14/2009 20:58:33.0478] [1] [ERROR] Setup cannot continue with upgrade because 'C:\Program Files\Microsoft\Exchange Server\V14\bin\ExchHelp.chm' is open. Close the file and restart setup. [11/14/2009 20:58:33.0494] [1] Ending processing. Thanks Steve