The. NET Framework 4.5 is contained in Windows 8 and is installed on your computer with the operating system. But. NET Framework 3.5 does not automatically install with Windows 81. To run an application that requires. NET Framework 3.5 on Windows 8, you must have version 3.5 enabled on your computer.
There are two ways you can do this by installing or running an application that requires the. NET Framework 3.5 (that is, by installing the. NET Framework 3.5 when needed), or by enabling the. NET Framework 3.5 in Control Panel. Two options require an Internet connection.
Use the. NET Framework 3.5 for Applications built for versions 2.0, 3.0, and 3.5.
Installing a Windows Language pack on Windows 8 that does not have the. NET Framework 3.5 installed will cause the. NET Framework 3.5 installation to fail. Before you install any Windows language packs, install the. NET Framework 3.5.
Windows CardSpace is no longer available with the. NET Framework 3.5 on Windows 8.
Manually install the required. NET Framework
If the application requires. NET Framework 3.5, but does not find an enabled version on your computer, it will display the following message box either at installation time or when you first run the application. In the message box, select Install this feature to enable the. NET Framework 3.5. This option requires an Internet connection.
Prompt to install the. NET Framework on Demand 3.5
Enable the. NET Framework 3.5 in Control Panel
You can also enable the. NET Framework 3.5 through Control Panel. In Control Panel, select Programs and features, select Turn Windows features on or off, and then select the Microsoft. NET Framework 3.5.1 check box. This option requires an Internet connection.
Enable or disable Windows features in Control Panel
If you install the. NET Framework 3.5 or if you have failed to enable it in Control Panel, you may receive one of the following error messages
0x800f0906: Windows cannot connect to the Internet to download the necessary files. Make sure you are connected to the Internet, and then click Retry to try again.
0X800F081F: "This change cannot be completed. Please restart your computer, and then try again.
These messages may be displayed for the following reasons:
Your computer is not connected to the Internet. Please connect, and then retry the operation.
If your computer cannot connect to the Internet, you can enable it by using the installation media (ISO image or DVD) from which Windows 8 is installed. NET Framework 3.5. Mount the Windows 8 installation media and type the following command from the elevated command prompt:
where x: is the drive letter of the Windows 8 ISO image or DVD.
Through the ISO installation method can refer to: http://win8e.com/jiqiao/7131.html
The local source is being used, but the network location is inaccessible or does not have the appropriate content. Enable the. NET Framework 3.5 from the installation media in the contents of the bulleted items described earlier.
Your administrator has configured your computer to perform services using Windows Server Update Services (WSUS) rather than using Windows Update. Ask your administrator to enable policies that use Windows Update rather than WSUS.