What you need is .NET Framework 3.5.1, which is actually .NET 2.0 with updates 3.0 and 3.5 with 3.5 SP1.
This framework comes with Windows 8.1, but is not automatically activated.
If you cannot find and activate .NET 3.5 by using Control Panel->Turn Windows Features on and off...
In the features list, find .NET Framework 3.5 (includes .NET 2.0 and 3.0), and ensure it is fully activated.
If that does not help, you can follow the procedure described here:
http://stackoverflow.com/questions/25188234/windows-8-1-unable-to-install-net-framework-3-5-0800f0906
