OK. Sorry. 
And as far as an answer: There's no way to know without you telling (whoever) what modulation those cable channels you aren't getting are using. If they're old-school NTSC (analog) channels, I *think* the answer then is "you bought the wrong tuner", because I *think* that the Mini Stick can only tune ATSC (over-the-air digital) and Clear QAM (over the wire digital), but CANNOT tune NTSC.
Good luck!
BittMann