Download Microsoft .NET Framework 3.0 Service Pack 1 from
Dec 11, 2017 Security and Quality Rollup updates for .NET Framework 3.5 Dec 11, 2018 Security and Quality Rollup updates for .NET Framework 3.5 Dec 11, 2018
.net framework 3.5 full package error in installation
Feb 21, 2011 Download .NET Framework | Free official downloads
Download the offline installer. The .NET Framework 3.5 SP1 offline installer is available on the .NET Framework 3.5 SP1 Download page and is available for Windows versions prior to Windows 10. Install the .NET Framework 3.5 on Demand. You may see the following configuration dialog if you try to run an app that requires the .NET Framework 3.5.
Microsoft .NET Framework 4.7.2 offline installer for Windows