I am trying in vain to install Blackberry Enterprise Server Express for Exchange Server 2007 on a Server 2003 Server that previously had Exchange 2003 Management Tools installed. I successfully removed the Exchange 2003 Management Tools, using add/remove programs, but there seems to be a residual side effect. When I now try to install the MS MAPI CDO 1.2.1 package, it acts like it installs (says it's successful), but never really does. There's no evidence of it in add/remove programs and the mapi and cdo files don't exist. Plus, Blackberry tech. support confirmed that it's not installing. They think it's a registry issue, but don't know how to fix. I'm stumped. It's driving me nuts. Anyone have any ideas?