Unarc.dll file issues only happen with pirated games.
These are the official MicroSoft forums (think about that), so as you might imagine it has rules against helping with
pirated (aka - 'repack') software\games. Asking for, or helping with piracy, can lead to a ban.
People don't often get reported (but a mod might lock the thread) unless they persist in asking for help though.
You would do better posting on your favorite pirate forums, as they would be better able to help.
btw - I see a mod helped you with another pirated game. That may have been because your machine picked up a malware\virus
that he wanted to help you with, not to fix the games Unarc.dll issue.