Greeting Stephan, Use another box, install exchange 2003, join existing org and move all mailboxes, public folders, system folders, smtp connectors/virtual servers to new server. The decommision the exchange 2003. Then demote DC. I rather re-install the whole box again. Make sure you have a clean member server. You could then install exchange 2003 again and move all back. It is lenghty but I realise it have mininimal downtime. This might help How to Move Exchange 2003 to New Hardware and Keep the Same Server Name http://support.microsoft.com/default.aspx?scid=kb;en-us;822945&Product=exch2 003 How to remove the first Exchange Server 2003 computer from the administrative group http://support.microsoft.com/default.aspx?scid=kb;en-us;822931 Make sure the Windows 2003 is completely patched before installing the exchange. Also use exchange 2003 sp1 Kind Regards Gill > -----Original Message----- > From: Stephan Barr [mailto:bdtsb@xxxxxxxxxxxxxxxx] > Sent: Tuesday, January 11, 2005 7:18 AM > To: [ExchangeList] > Subject: [exchangelist] Re: Exchange 2000 isn't recognizing > domain user logins. Can't connect with OWA or Full Outlook > > http://www.MSExchange.org/ > > The Exchange server is a DC; any experience with demoting while an > Exchange instance is installed? I'd love to get AD off there. > >