Help Please! How to resume download after HD formated?

I just formated my HD due to some speed issues, and I did back up everything in Bitcomet folder. but after I reinstalled evertything back, all tasks start download from 0%, does anyone know how to resume previous download? I did what the fourm said, open previous torrents and use the same dir, but it still satrs from 0%. Please help! Thanks

You have to hash check the files again.

right click on the torrent tasks and select manual hash check