Make sure you have a fully updated Windows 2008 64bit install setup for the following commands to work. Note that Windows 2008 R2 will NOT work with Exchange 2007.
Exchange 2007 has a lot of prerequisites that need to be installed before you can install Exchange 2007. Instead of going through a bunch of Wizards and using trial and error to make sure you have everything installed, you can set them up using a command line.
The first command that should be run is:
ServerManagerCmd -i PowerShell
This will install and configure everything that Exchange 2007 needs for PowerShell.
IIS has several components that need to be installed to use Exchange 2007. You can create a quick batch script that includes them all. The following commands need to be run:
ServerManagerCmd -i Web-Server
ServerManagerCmd -i Web-ISAPI-Ext
ServerManagerCmd -i Web-Metabase
ServerManagerCmd -i Web-Lgcy-Mgmt-Console
ServerManagerCmd -i Web-Basic-Auth
ServerManagerCmd -i Web-Digest-Auth
ServerManagerCmd -i Web-Windows-Auth
ServerManagerCmd -i Web-Dyn-Compression
If you plan on using RPC over HTTP (Outlook Anywhere) you will need to run this command after all of the IIS commands have finished:
ServerManagerCmd -i RPC-over-HTTP-proxy
After running these commands you should be ready to run the actual setup files. When you run setup.exe you should see that everything before option 4. Is greyed out. Option 4. is what triggers the install. If anything has not finished look through the command lines to make sure no errors have shown up.