Similar problem here. I did install that prereq thing first and still the same error. I'm also on Windows 7 as the other poster.
Viewing post in Cactus (Prototype) jam comments
It seems like this is an issue with UE4's engine code and it won't be fixed until the next UE4 hotfix/release. https://forums.unrealengine.com/unreal-engine/feedback-for-epic/1758469-unreal-engine-4-25-and-windows-7-compatibility