Errore 0x800F0906 durante l'attivazione di .net 3.5 in Windows 8.x

Nel  caso compaia il seguente errore durante l'attivazione della funzionalità .net 3.5

Windows couldn’t complete the requested changes.
Windows couldn’t connect to the Internet to download necessary files. Make sure you are connected to the Internet, and press “Retry” to try again.

Error code: 0x800F090

Fix:

1. Open Windows Explorer (Windows + E)
2. Mount the Windows 8 installation ISO you used to install your operating system. You can do this by right clicking on it and selecting the option Mount. UPDATE: If you have the Windows 8 Installation Disc in your optical drive, then use this instead. However, make sure you change the commands mentioned later to match your optical drive.
3. Use the RUN command in administrator elevated mode. You can do this by navigating to the location c:\windows\system32\cmd.exe and right-clicking on the cmd.exe application and selecting Run as administrator.
4. Once the command windows has loaded, then type the following command (Note: Match the drive letter to your appropriate drive letter for the ISO or DVD):