App is slow and wont scan external HD

But this app recently for $9,99 and now its $4,99. Considering the fact that this app doesnt even scan external HD’s and the Trend Micro Inc company does NOT respond to emails you send them, I classify this App 2 stars aswell as a ripoff. I reported these problems directly to Apple, I hope I get my money back. Dont buy is my advice.

Horserious about Duplicate Finder - File Clean