The current version of UE4 doesn’t support update 3 of VS2015.
More info here: Build Failed with VS 2015 update 3 - Programming & Scripting - Epic Developer Community Forums
I didn’t see an announcement or anything anywhere on the forum so I figured I would make a post to help some people avoid headache.
If anyone knows of a way to revert to update 2, let me know.
Hm I thought that even Update 2 breaks everything in UE 4. I’m still using VS with Update 1 
Control Panel -> Programs -> Programs and Features -> Installed Updates -> find the one you don’t like -> Uninstall
Are you some kind of wizard? Thanks a ton, man. I couldn’t find this anywhere… I feel like an idiot.
For some Reason this doesnt works for me after a week of trying everything i could find on the Net, I uninstalled UE4 completely. Makes no sense under this circumstances. 
Lol for some Reason Windows now decided to uninstall the update and everything is fine again…
Update 2 works, but update 3 broke everything even after uninstalling it (the update only)
Any ideas when things will work with update 3?
I tried this but it didn’t work:
https://github.com/Neurochrom/UnrealEngine/commit/89ab7a08af165cad02073261b4b8e7af61a63d2c
I think I’ll have to do this
Blam is right
Weird, for some reason my VS2015 Update 3 works just fine with UE4 
4.12.5 apparently fixes the issues with Visual Studio 2015 Update 3.
4.14 broken again