The following bug has been logged online:

Bug reference: 1946
Logged by: Pedro Alvarez
Email address: pt (AT) dti (DOT) cz
PostgreSQL version: 8.0.4
Operating system: Windows XP SP2
Description: Service registration fault during upgrade installation
Details:

During upgrade from 8.0.3 to 8.0.4 installation procedure doesn't care about
your database location and set it to default. In that case your server won't
start until manual repaire.

Steps to reproduce:

prerequisities) Have a running version (e.g 8.0.3 or any which can be
upgraded by latest setup), using different database location path, using NT
Service for startup

1) Start upgrade by upgrade.bat

2) Try to start service

3) Check service setting in Service console

---------------------------(end of broadcast)---------------------------
TIP 9: In versions below 8.0, the planner will ignore your desire to
choose an index scan if your joining column's datatypes do not
match