Newbie installation problem: non 7-zip archive

["Angus Monro" <angusmonro@people.net.au>]

Hi,

I’m just looking at GIT for the first time, but can’t get past first base.

I’m working on Win XP 2002 SP3.  

When I download & run PortableGit-1.6.2.1-preview20090322.exe, it asks for
the installation location, but after I’ve confirmed that location & pressed
OK, it gives me an error message window:
     Title bar:   “WinGit: MinGW Git + minimal MSys installation: error”
     Message:     “Non 7-Zip archive.”

When I download & run Git-1.6.2.1-preview20090322.exe, it immediately
complains
     Title bar:   “Error”
     Message:     “The setup files are corrupted.  Please obtain a new copy
of the program.”

In both cases, I’ve downloaded from
http://code.google.com/p/msysgit/downloads/list, and have tried
re-downloading & re-running, still without success.

Any thoughts?

Thanks,

Angus Monro.