To install this package, you must use elevated command-line tools. Standard GUI methods often fail if the system cannot reach Windows Update . 1. Deployment Image Servicing and Management (DISM)

Always extract the CAB from or from the official Microsoft Update Catalog (search for “Feature on Demand v2 - .NET Framework 3.5”).

Historically, Windows installed almost every optional feature by default. This resulted in a bloated operating system with a large attack surface. Modern Windows versions utilize a "OneCore" base, where optional features are stripped out and hosted on Windows Update servers or installation media. These are known as .

There is with "-Extra" in its name. However, system integrators sometimes create custom bundles and add "Extra" to denote that the package also contains SQL Server Compact or obsolete WCF components.