Every time I try to build lights (both for templates and custom projects) the editor crashes.
Everything works fine, building geometry works as it should, but for some reason each time I try to build lights the Editor crashes immediately.
This problem first appeared after I had to format my C drive and re-install a clean Win7.
I was using UE4 on this same hardware with the same system version before and did not have any problems with the engine running.
Any ideas as to how to fix this?