During the game or startup XCOM 2 an error Unarc.Dll.
Error This in XCOM 2 going because lack components for your operating system Windows.
Fix Error Unarc. Dll can, you need install the Package winsdk_web , when you update them rerun the XCOM 2 and Unarc.Dll error You will not disturb.
Win SDK he scans your OS windows and update all missing elements.