When I try to uninstall Exchange 2003 from a SBS 2003 Intallation I get on the pre-requisits check an error like (translated from German) "You have to be a member of Domain Administrators, Schema Admin and Orgnisations Admin". From this point on I only can skip the installation. Actually this wasn't like that all the time because I already managed to uninstall Exchange 2003 this way, but it seems to not have completelly uninstalled since the services are still in place and also AD seems to be aware of this server as having an Exchange role. Interesting enough, the OS itself doesn't seem to complain very much because of this half-way uninstalled Exchange server, in the EventViewer logs I do not see much about the fact that on one hand exchange services are still there, on the other hand it's not functional anymore... The Exchnge snap-ins from MSC have also been removed, the server cannot be contacted by best practice analyzer of the 2010 anyomre etc... So it looks like most of the Exchange 2003 has been removed, but it has not cleanly unregistred form AD.
I used the build-in Administrator account for uniinstallation, it is a member of the mentioned groups. It is not a member of guests, mobile users or such groups. All I can imagine is that because this Administrator is still a member of some other groups
too, like about 6-7 other self-created groups mainly, this might confuse the uninstall check engine. But as I said, just 20 minutes ago it worked whith the same group membership of Administrator, then not anymore, than again and now not anymore again. The
first time I got this error the Adminstrator was indeed a member of mobile users, I removed it from there and then the check went through. But now this doesn't anymore, I think it was just a coincidence tht it immediatelly worked once after removing Administrator
from mobile users.
One more thing, I created a new admin beeing solely member of these three groups, tried to use that one, but there the uninstall complains that I have to use the built-in Administrator, though.
I have an Exchange 2010 Server running on a different W2k8 R2 Server which is my main Exchange server since almost 2 years. Everything is moved over since long time. But when I call "get-exchangeserver" cmd-let on this 2010 I still see the old 2003
SBS exchange.
I may remove Exchange now following the instructions from here http://windowsitpro.com/exchange-server/how-uninstall-stubborn-exchange-server - but I'd rather do this in a clean way.
All I want is actually to achive that my AD + Exhcnage environment doesn't feel like this old 2003 Exchange should still be here. As a next step I'd like to move the FSMO roles and remove the SBS 2003 Domain Controller.