It took me a bit of time to get this resolved, so i figured I'd post it here just in case anyone else had the same issue. I always get an error when updating the game. This only happens on my SSD and not my old HDD. I have windows 7 ultimate 64bit on both drives. For some reason SearchIndexer.exe is using my files right when they get downloaded, then I get the error. So I simply open task manager, end process SearchIndexer.exe, and try installing again and it works fine. Hopefully this info helps at least one player.