Just a word to help any poor bastard who might be trying to install postgre SQL on a Windows box. Not only should you read the documents but be certain the "Secondary Logon" service has not been disabled. I spent waaaay to long trying to get this installed on a server managed by our new hosting company and eventually tracked it down to the fact that this service had been disabled for security reasons. Turns out that during install it needs to execute some scripts as the non privileged user and it relies on this service to execute the code as that user. Unfortunately the error returned bears no relationship to the problem.
I'm sure that almost no one will need this info but trust me, if you do, you will be very happy to know this.

mike