: If your computer has internet access, you don't even need the CAB file. You can simply go to "Turn Windows features on or off" in your Control Panel and check the box for .NET Framework 3.5 . How to Install Using the CAB File
Do not use unofficial download links for system files. If you have an internet connection, the easiest way to install .NET 3.5 is through "Turn Windows features on or off" microsoftwindowsnetfx3ondemandpackagecab download free link