Retail PC copies of the highly anticipated Call of Duty: Black Ops II come with second installation discs. That may seem perfectly normal, but these discs seem to contain data for BioWare’s Mass Effect 2. People everywhere, from Steam to Reddit, have been talking about this issue. There’s even a video on YouTube showcasing the huge blunder. PC players aren’t completely out of luck, however, because the game can still be installed (albeit, very slowly) with a Steam key that comes with each copy.

One has to wonder though–how, exactly, do you go about making such a careless mistake like this? Check out the YouTube video here (warning: there’s excessive profanity).