Windows Update Agent

I need to update my msn to 8.5
but before that it says to have Windows Update Agent version 5 or later ..

i went here
http://jalaj.net/2008/01/20/downloading-windows-update-agent-5802469/

and downloaded
http://download.windowsupdate.com/WindowsUpdate/redist/standalone/7.0.6000.381/WindowsUpdateAgent30-x64.exe
for second time... but when i tried to install it .. it says ... that's not win32 application ...

????

i think the download is not good ...
where could i get a fresh copy of download ...