Travel dilemmas: Why you aren't getting TSA PreCheck?

You completed your application for PreCheck, the faster-through-security program from the Transportation Security Administration, paid your $85, did the interview, got the OK and your flying life should be a bed of roses. But you aren't getting PreCheck. It doesn't show up on your boarding pass. Here may be some reasons you're still with the huddled masses who must remove their liquids and their laptops from their carry-on, take off jackets and shoes and then reassemble.

- You didn't enter your Known Traveler Number, or KTN, when you made your airline reservation. TSA doesn't