FYI~
1.) Stop All Exchange Services.
2.) You will need to remove the following registry keys: Under HKEY_LOCAL_Machine\System\CurrentControlSet delete the following: All MSExchange* keys msftesql-Exchange msftesqlFD-Exchange msftesqlIDX-Exchange Delete the HKEY_LOCAL_Machine\Software\Microsoft\Exchange Key
3.) Delete All Exchange Binaries, by default the binaries are installed here: C:\Program Files\Microsoft\Exchange Server Note: Please make a copy of any Exchange Databases and logs if necessary and copy the queue directory (default: C:\Program Files\Microsoft\Exchange Server\TransportRoles\data\*) (need to verify) All Database directories should also be deleted (or moved to a safe location) these could be located on other drives.
4.) Remove and reinstall the Internet Information Services (IIS).
5.) Remove Exchange 2007 configuration server object in Active Directory. Using ADSIedit locate the server Object: CN=Configuration, DC= Domain_Name ,DC=com, CN=Services, CN=Microsoft Exchange, CN= <Organization_Name>, CN=Administrative Groups, CN= Exchange Administrative Group (FYDIBOHF23SPDLT), CN=Servers, CN=<Server Name>
6.) Remove the server’s machine account from all Exchange groups: Exchange Servers and Exchange Install Domain Servers.
7.) Remove the Exchange Organization Group from the local machine’s Administrator Group.
8.) Right Click on the Exchangeserver.msi file and select uninstall.
9.) If the removed server had replicas of the OAB or was the OAB generating server, the replicas will need to be homed onto another Public folder server and the OAB generation server will need to be changed using the Exchange Management Console.
10.) If the server was an endpoint for any connectors these will need to be re-homed to an existing Hub Transport (HT) server or deleted and recreated on another HT server.