How to Offline Install .NET Framework 3.5 in Windows 11 with DISM

This post will show you how to install .NET Framework 3.5 in Windows 11 offline from an installation media with DISM. By default, Windows 11 only includes .NET Framework 4.8. However, there are still a huge number of useful apps built against the .NET framework v3.5.

Such apps were created for Windows 7 and even for Windows Vista, where version 3.5 was available out of the box. Once you try to run such an app, you will see a prompt to install the missing component from the Internet.

This method has a number of disadvantages. First of all, it is your Internet traffic, and it can be limited. Secondly, the download process is not reliable and can fail. If your Internet connection is unstable, it turns into hell. Finally, you can simply work offline.

That's why it is important to know how to offline install .NET Framework 3.5 in Windows 11. You will only need an installation media of Windows 11, such as ISO file, bootable flash drive, or its DVD disk, so no Internet connection will be required.

To offline install .NET Framework 3.5 in Windows 11, do the following.

Install .NET Framework 3.5 in Windows 11 Offline

1. Double click the Windows 11 ISO image, or plug your bootable flash drive or insert DVD disk with Windows 11.
2. Open File Explorer (press Win + E) and navigate to the This PC folder. Note the drive letter of your installation media have inserted. My drive is G:.
3. Now open Windows Terminal as Administrator by selecting Windows Terminal (Admin) from the Start button's right-click menu.
4. Switch Windows Terminal to the Command Prompt profile; press Ctrl + Shift + 2 or the arrow menu button.
5.  In the command prompt tab, type the following command: Dism /online /enable-feature /featurename:NetFX3 /All /Source:G:\sources\sxs /LimitAccess. Replace G: with your Windows 11 setup media's drive letter and hit Enter.

You are good to go! This will install .NET framework 3.5 in Windows 11 without using any Internet connection.

Now you can run any older apps coded in C#, VB.NET, and C++ that are built around older versions of the software platform. Note that .NET Framework 3.5 also includes .NET 2.0, which is also the runtime version.

Using a batch file

To save your time, I have created an easy-to-use simple batch file which automates the above method. It will automatically find your Windows 11 installation DVD disk or USB drive.

To install .NET Framework 3.5 on Windows 11 with a batch file, do the following.

1. Download this ZIP file.
2. Extract the CMD file it from the ZIP archive to the Desktop.
3. Connect or insert your Windows 11 installation disk.
4. Now, right-click the cmd file and select Run as administrator from the menu.
5. The cmd file will auto-detect Windows 11 setup disk and instantly add .NET Framework 3.5 automatically.

You are done. The file is compatible with both install.wim and install.esd - based setup media types of Windows 11, so you can use any! The official one comes with install.esd by default.

Batch file contents

The contents of the batch file are listed below.

@echo off
Title .NET Framework 3.5 Offline Installer
for %%I in (D E F G H I J K L M N O P Q R S T U V W X Y Z) do if exist "%%I:\\sources\boot.wim" set setupdrv=%%I
if defined setupdrv (
echo Found drive %setupdrv%
echo Installing .NET Framework 3.5...
Dism /online /enable-feature /featurename:NetFX3 /All /Source:%setupdrv%:\sources\sxs /LimitAccess
echo.
echo .NET Framework 3.5 should be installed
echo.
) else (
echo No installation media found!
echo Insert DVD or USB flash drive and run this file once again. 
echo.
)
pause

Tip: You can easily find what versions of the .NET framework software you have installed using the following guide.  It will give you ideas what apps will work on your computer without installing additional system components.

Finally, if you don't have the installation media for Windows 11, and also have no troubles with the Internet, you can give the online .NET Framework installation a try. Since we have already mentioned it in the post, let's review it for the sake of completeness.

Install .NET Framework 3.5 with Optional Features

1. Press Win + R to open the Run box and type optionalfeatures.
2. In the Windows Features window, select the .NET Framework 3.5 (includes .NET 2.0 and 3.0) entry.
3. Enable it by placing a check box and click on the OK button.
4. Wait for Windows 11 to download and install the components.

You are done. So, as you can see, it is an optional component of Windows, so you can manage it like any other optional feature. Microsoft also recommends using this method by default.

That's it.