During the BizTalk installation process (from 2006 versions to the current latest one: 2009 R2) the Microsoft BizTalk Server Installation Wizard will ask you for the CAB file containing all the prerequisites needed.
Most of the times production servers do not have access to internet, so you will need to select “Automatically install the redistributable prerequisites from a CAB file” (obviously i never recommend the first option since sounds the crazy one)
Right, but the point is… where to download the CAB from?
In my case i ever forgot to add the link to favorites 😉
As showed in the picture above, there is an always-omitted-great-help-button. Click on it!
The help file will be opened showing, grouped by operative system version, where to download the CAB file from!