Do you have Adobe Reader 9.0 or 9.3?
If you have 9.0, download the 9.3 installer first
If/once you have 9.3 installed, download the 9.3.1 update
I tried following your links and installing but keep getting error 1303 when trying to install the setup. Any ideas what it is and why I'm getting it? Thanks for your help. Marsha