Keep a Windows 11 USB drive handy. With the simple DISM command above, you can enable .NET 3.5 on any offline Windows 11 machine in under five minutes, ensuring your classic applications run smoothly without an internet connection. Have a question about deploying .NET 3.5 across multiple offline machines? Let us know in the comments.
Inside the mounted drive, navigate to the sources\sxs folder. You should see a file named microsoft-windows-netfx3-ondemand-package.cab . This is the offline source. .net 3.5 offline installer windows 11
Type the following command, replacing D: with your mounted drive letter: Keep a Windows 11 USB drive handy
If you are a developer, a gamer running classic titles, or an enterprise user maintaining legacy software, you have likely encountered the dreaded prompt: “This application requires .NET Framework 3.5.” Let us know in the comments
Copy the ISO to your offline Windows 11 PC (via USB). Double-click the ISO file to mount it as a virtual DVD drive. Note the drive letter (e.g., D: ).
While Windows 11 comes with .NET Framework 4.8 (and newer) pre-installed, version 3.5 (which includes 2.0 and 3.0) is not enabled by default. The most common method to install it is via Windows Features during an active internet connection, but what if your PC is offline, on a restricted network, or the online download keeps failing?
Open Command Prompt as Administrator (right-click Start button > Terminal (Admin) > choose Command Prompt).