By default the .Net 3.5 framework is not installed on Window 8 and 8.1. When enabling the feature it will download the needed files from Windows Update. If you have a slow or no internet connection it can be useful to install .Net Framework directly from the Windows 8 DVD.

Offline .Net Framework 3.5 Installation

  1. Insert the Windows 8.1 installation media
  2. Open an administrative cmd prompt or PowerShell
  3. Run the following command

 

 

Assumes Windows 8.1 media is at “d:".