I was having some serious trouble installing Lego City Undercover to my usb hard drive. At 18GB, it's the largest game I own. I kept trying to install the game, and it failed 3 times in a row. I finally just tried to install it to system memory. It installed without any issues. I thought I could just copy the game from system memory to my hard drive once this was done. This failed at almost exactly the same point Wupinstaller was having trouble. I decided to try switching to a different enclosure for my drive at this point. Sure enough, things started working correctly.
Long story short, make sure you're using a reliable drive enclosure!
Long story short, make sure you're using a reliable drive enclosure!