I did some additional searching on the generic issue, not related to roborun, as other installers have similar issues...
1. Go to Control Panel->Programs and Features
2. Click the link on left side called: "Turn Windows Features On or Off". A dialog will open.
3. At the top of the list, I see an item called ".NET Framework 3.5 (includes .NET 2.0 and 3.0)". Check it and there will be a square in the box.
4. Press OK. Follow the instructions to let Windows install/configure the necessary updates. Done.
5. Try installing Roborun again.