On default, Windows 8 has shipped .NET Framework 4.5, installed and available. However, some app requires a specific version of .NET version. If the .NET version is lower than the provided (for example 3.5, like we want to discuss here) the app will fail to run. You will also be prompted to install .NET framework.
To run apps that require the .NET Framework 3.5 on Windows 8 or later, we must enable it. There are three ways to do it, two online method, and one offline method. The first two methods involves internet connection therefore you should present the Internet Access. The last method will do offline installation, what you need is Windows 8 installation CD.
Note that this instruction also apply to installing the .NET Framework 3.5 on Windows 8.1.
A special caution, any versions of .NET Framework should not be uninstalled from computer because there might be one or many app depends on a specific version and may break if that version is removed.
Multiple versions of the .NET Framework can be loaded on a single computer at the same time. This means, you do not have to uninstall previous version in order to install the later version.
On Demand Installation
In most case, if an app requires .NET Framework 3.5 and doesn’t find the version enabled on computer, it display a message box. The box will appear either during installation or when running the app for the first time. To enable the .NET framework 3.5, choose “Install this feature”. This option require internet connection.
Enabling .NET Framework 3.5 in Control Panel
The .NET Framework 3.5 can also be installed through Control Panel. Choose “Programs and Features”, then “Turn Windows features on or off”, and then select the “.NET Framework 3.5 (includes .NET 2.0 and 3.0)” checkbox.
You don’t need to select the “Windows Communication Foundation HTTP Activation” nor “Windows Communication Foundation Non-HTTP Activation” unless you are a developer who requires WCF script and handler mapping functionality.
Install by DVD
You need your Windows 8 installation DVD. If you are using ISO image, mount it. Make sure you remember the path / drive letter your disk (or image) is. In this article we will use G:\ as the example.
Open an Command prompt as administrator. You can do this by press start, type cmd which will give you some options. Navigate to Command Prompt and right click it. A new bar will appear, let’s click on “Run as administrator”.
Then we have a command prompt with escalated privilege.
Next, invoke following command. Assuming the DVD drive (where the DVD is) is G:\.
DISM.exe /Online /enable-feature /featurename:NetFX3 /Source:G:\sources\sxs /LimitAccess
After the installation finish, you will have the Microsoft .NET Framework 3.5 installed.