2012 - How to install .NET 3.5 Framework

During these years I had necessity to install .NET 3.5 framework on server 2012 R2/Windows 10.

One problem that I faced was that DVD installation media was unable to locate installation binaries and server/client relates to WSUS server (that it hadn't binaries).

To discard WSUS pointing and to force internet download binaries you need register key change and us proper command.

Here they are some errors prompted:

Windows couldn’t complete the requested changes.

The changes couldn’t be completed. Please reboot your computer and try again.

Error code: 0x800F0954

Executing this command

DISM /Online /Enable-Feature /FeatureName:NetFx3 /All

C:\Windows\system32>DISM /Online /Enable-Feature /FeatureName:NetFx3 /All

Deployment Image Servicing and Management tool
Version: 6.3.9600.19408

Image Version: 6.3.9600.19397

Enabling feature(s)
[===========================66.6%======                    ]

Error: 0x800f0906

The source files could not be downloaded.
Use the "source" option to specify the location of the files that are required t
o restore the feature. For more information on specifying a source location, see

The DISM log file can be found at C:\Windows\Logs\DISM\dism.log

Fix is to:
  1. Execute regedit.exe with Administrative rights.
  2. HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WindowsUpdate\AU
  3. Search for UseWUServer and set it to 0
  4. Restart PC/Server.

More information could be found at below article: