I’ve been working with Windows Server 8 Beta quite a bit recently. One of my major frustrations with it is that I couldn’t enable the .Net 3.5 Framework. When I would try to enable it within the Server Manager, it would error out that it couldn’t download it. Without this, I couldn’t install several Microsoft programs (SQL Server 2008/2012, Visual Studio 2010, etc, etc). After quite of bit of searching, I finally figured out a workaround.
Insert the Windows 8 installation DVD (I’ll assume it’s your D: drive). Open a command window (runas Administrator), and enter in the following:
Dism /online /enable-feature /featurename:NetFX3 /All /Source:D:\sources\SxS /LimitAccess
And that’s it!