/enable-feature /featurename:NetFX3 : Specifies the installation of .NET Framework 3.5.
If using /quiet , the command prompt will return without output. To verify success:
This is the fastest method and less prone to GUI timeouts. Ensure your installation media is mounted. powershell # Replace 'D:' with your actual drive letter
# Install .NET 3.5 from the CAB file dism /online /add-package /packagepath:"C:\Temp\microsoft-windows-netfx3-ondemand-package.cab"
Execute the following command pointing exactly to the folder containing your CAB file: Ensure your installation media is mounted
Here are the two most reliable methods:
Installing .NET Framework 3.5 on Windows Server 2012 R2 often triggers the infamous "source files could not be found" error. This happens because the installation files for .NET 3.5 are not included in the local side-by-side (SxS) store of the operating system to save disk space. Instead, the OS relies on Features on Demand (FoD) to fetch these files.
Deployment Image Servicing and Management tool Version: 6.3.9600.17031
http://download.windowsupdate.com/d/msdownload/update/software/updt/2015/11/microsoft-windows-netfx3-ondemand-package_421a25bf409692045d1cbfab0d99f8def8d95d3f.cab Instead, the OS relies on Features on Demand
: Inside that folder, you will find microsoft-windows-netfx3-ondemandpackage~31bf3856ad364e35~amd64~~.cab . Copy this file to a local directory on your target server, such as C:\sxs\ .
The specified source path does not contain the correct version of the CAB file.
The most reliable method to fix this "file not found" error is to use the Deployment Image Servicing and Management (DISM) tool. You will need access to a Windows Server 2012 R2 ISO file or a USB/DVD drive.
If prompted, download and install the .NET Framework 3.0 On-Demand Package CAB. such as C:\sxs\ .
Insert or mount the Windows Server 2012 R2 installation media. Assume the drive letter is D: . Open PowerShell/CMD: Open as Administrator. Run DISM Command: Execute the following command: powershell
What the CAB Is
Method 2: Using the .CAB File Directly (Offline/Alternative)
$cabPath = "C:\Deployment\microsoft-windows-netfx3-ondemand-package.cab" if (Test-Path $cabPath) Write-Host "Installing .NET Framework 3.5 from CAB..." dism /online /add-package /packagepath:$cabPath /quiet /norestart Write-Host "Installation completed. Reboot may be required." else Write-Error "CAB file not found at $cabPath"
After installation, verify success: