.NET 3.5 is only available from windows update and we use WSUS. You must make a change in the local machine GP editor to allow contacting windows update.
The Group Policy on the machine is not allowing Windows Update to download and install the .NET Framework 3.5.
Step 1 – Change the Group Policy
- Type gpedit.msc in RUN or Start search box and press Enter. It will open Group Policy Editor.
- Now go to: Computer Configuration -> Administrative Templates -> System
- In right-side pane, find the option, "Specify settings for optional component installation and component repair".
- The option would be set to Not Configured. Double-click on it, and set it to Enabled and enable the "Contact Windows Update directly to download repair content instead of Windows Server Update Services (WSUS)" option. This option may be worded slightly different.
Step 2 – Enabling the .NET Framework 3.5 to be downloaded and installed
- Go to your Control Panel - > Under Programs click Uninstall a program
- In the “Programs and Features” window, click on the link “Turn Windows features on or off” on the left hand panel.
- Check the box next to the “.NET Framework 3.5 (includes .NET 2.0 and 3.0)” to enable it and then click on “OK”.
- Choose the option to “Download files from Windows Update”