I'm trying to install my fist Exchange 2003 Enterprise server. I already have a running Exchange 5.5 on a Win 2k server. My domain has been upgraded from NT to 2003. After successfully completing all the pre-install steps to Coexist with Exchange 5.5 when I run the setup.exe I get the following error: (Setup encountered an error while checking prerequisites for the component "Microsoft Exchange": 0XC103FC93 (64659): Unable to find object /o=<OrganisationName>/ou=<Site>/cn=Configuration/cn=Servers/cn= <decomissioned exchange 5.5 server name/cn=Protocols/cn=LDAP.) The server it is looking for has been long decomissioned. And though I didn't do a good job of uninstalling it I had to run admin -r to remove some instances left in my current Exchange 5.5 server. Is there a work around to make setup.exe not look for the deleted exchange server. Thanks for a quick responce in advance.