James,
that error is well documented in the PGINSTALLER-FAQ on pgfoundry.
Problem: "something" is interfering with socket-inheritance.
"something" most offen is some kind of "Layered service provider" as
is: Antivir software, Age Verfication Software..."
Workaround now: "something" has to be uninstalled
"solution" longterm 1: "something" has to be changed to respect the
specification
solution longterm 2: there is a quite complicated patch available for
the win32-socket code. I someone with enough win32 socket programming
excellence AND available time is willing to donate that time and
excellence to postgresql ... that workaround might be implemented.
Harald