Unable to download the Web Platform product list from . Check your network connection and try again. If the problem persists, report the issue on the Web Platform Installer forum at: http://go.microsoft.com/fwlink/?LinkId=145244.
Applies to Web platform installer 3 on server 2008
Verify you can browse to http://www.microsoft.com/web/webpi/3.0/WebProductList.xml
If you can then add the following registry key
HKLM\SOFTWARE|Microsoft\WebPlatformInstaller
Add string value (reg_sz) named "ProductXmlLocation"
Value http://www.microsoft.com/web/webpi/3.0/WebProductList.xml
Re run the Web Platform Installer and all should be well
Thank you so much ! This worked like a charm. For this interested, I run a Windows 2008 Server and had the above described problem.