Apologies in advance if this is in the wrong section.

I have a custom application that makes a Windows self-extracting cabinet file containing a single exe (called client.exe) and a INF file to copy that exe to a particular point on the disk.

This INF file is generated automatically depending on the client that connects to the system and it installs correctly on Windows XP however on Vista it returns the helpful error message "Installation Failed" then continues to run the Post-Install command defined in the sed file.

A sample of one of the generated INF files is below:

[Version]
Signature=$Chicago$
Provider=%Author%
SetupClass=BASE
Compatible=1
Generator=INF-Tool v6.3d Lite

[Strings]
Product="Product 1"
Version="1.0"
Author="Me"
Copyright=" 2007 by Me"
DiskName="Product 1, Setup Disk #1"
Setup="SOFTWARE\Microsoft\Windows\CurrentVersion\Setup"
[SourceDisksNames]
1=%DiskName%,,0
[SourceDisksFiles]
Client.exe=1
[DestinationDirs]
CopyGroup=-1,"C:/Test"
[DefaultDestDir]=-1,"C:/Test"
[CopyGroup]
Client.exe,Client.exe,,0x00000001
[DefaultInstall]
Copyfiles=CopyGroup

The directory C:/Test is guaranteed to exist.

This works correctly on XP Professional and Home variants but Vista gives an "Installation Failed" message (and doesn't copy the file).

Any tips?