Windows Installer

Hello,
I am not succeeding in the installation of postgresql on a win2000 box.
I cannot find a specific list for Windows installer problems. If there
is one I would appreciate being directed to the appropriate place.
Description follows: -
System: Win2000 SP3 NTFS file system
All non-essential services stopped.
All user programs stopped.
All virus checkers and services stopped.
Invoking postgresql-8.0.msi results in
"Error reading from file C:\TEMP\postgresql-8.0.3\postgresql-8.0.msi
verify that the file exists and that you can access it"
Nevertheless installation proceeds to final install screen when: -
"Error reading from file c:\TEMP\postgresql-8.0.3\postgresql-8.0-int.msi
verify that the file exists and that you can access it"
The installation aborts at this point.
I have a log file that is 220Kb if someone wants to view it.
Can any person assist?

Regards
John Craddock