Ok, here is the current situation. We are currently running an Exchange 2003 server setup with two domain controllers, and we decided to go over to Exchange 2007. One of my colleagues managed to install Exchange 2007, but then, for some reason, decided that he hadn't run some of the setup features (/preparead) and so decided to uninstall Exchange 2007. But instead of being patient and uninstalling everything properly, he got halfway through and then formatted the Exchange 2007 server. Now wheneverI try to install Exchange 2007, I get an error message of "Exchange Server Setup has encountered an error", which I have come to loathe. This error appears no matter what method I use to try and install Exchange 2007 - if I try to run setup /preparead, or any other switches, I get the same result. Here is the Exchange Setup Log: [26/07/2007 11:10:07] [0] **********************************************[26/07/2007 11:10:07] [0] Starting Microsoft Exchange 2007 Setup[26/07/2007 11:10:07] [0] **********************************************[26/07/2007 11:10:07] [0] Setup version: 8.0.685.25.[26/07/2007 11:10:07] [0] Logged on user: mydomain\Administrator.[26/07/2007 11:10:07] [0] Command Line Parameter Name='nologo', Value=''.[26/07/2007 11:10:07] [0] Command Line Parameter Name='preparead', Value=''.[26/07/2007 11:10:07] [0] Command Line Parameter Name='sourcedir', Value='D:\'.[26/07/2007 11:10:07] [0] Command Line Parameter Name='fromsetup', Value=''.[26/07/2007 11:10:07] [0] ExSetup was started with the following command: '/NoLogo /preparead /sourcedir: D:" /FromSetup'.[26/07/2007 11:10:08] [0] Setup is choosing the domain controller to use[26/07/2007 11:10:08] [0] Setup is choosing a local domain controller...[26/07/2007 11:10:10] [0] Setup has chosen the local domain controller osiris.mydomain.net for initial queries That is it in its entirety. In the event viewer, I get errors 2152 and 4999. Any help would be greatly appreciated - our Microsoft Licence is due to run out at the end of July!

Now worries- I cleaned up DNS, AD and just about everything else on my Domain Controller, but was still getting error 2152. I read up on these forums about deleting the profile, so tried this and it worked! So thanks to everyone on various other threads that suggested that fix.

Fixed it. After extensive cleanup of DNS, AD and just about everything else on the DC, I was still stuck with error 2152. So I read up on these forums about a fix for it - deleting the local profile and restarting - and it worked! So thanks to everyone who suggested that fix in other threads.