Mistake # 30: Never ask anyone what kind of tree they want to be.
It was 25 years ago when Walters asked Katharine Hepburn that question. It's a moment that has dogged her throughout her career.
Mistake #29: Never gush over a future president.
A sappy good night to then-President-elect Jimmy Carter and his wife, Rosalynn, on her very first special in 1976, is a clip that still makes Walters cringe.
Mistake #28: It's one thing to ask about embarrassing pictures, it's another thing to embarrass a guest.
Walters asks numerous women why they posed nude for a magazine, but with Suzanne Somers she takes the questions a little too far.
Mistake #27: Never ask people how much they're worth, it's rude. … Unless it's Donald Trump.
Forget not talking about money: Walters has asked celebrity after celebrity about their financial status — even 11-year-old Dakota Fanning.
Mistake #26: Enough already with the virginity talk!
Walters discusses losing one's virginity with leading men Patrick Dempsey, Don Johnson, Ricky Martin and Liam Neeson.
Mistake #25: If you're beautiful, stop saying you're not. It's irritating to the rest of us.
This mistake was made by some leading ladies, when Walters asked Hollywood beauties like icon Lauren Bacall and Halle Berry how they really feel about their looks.
Mistake # 24: If you don't think someone is sexy or attractive, don't say it.
In humorous conversations with Bette Midler and Tom Hanks, Walters is a little too honest about her opinion of their looks.
Mistake # 23: Never turn down dinner with Clint Eastwood.
Walters shares how she let a date with Clint Eastwood slip through her fingers.
Mistake #22: Sitting down with your mate can lead to trouble.
In another mistake attributed to her guests, celebrity couples such as Michael Douglas and Catherine Zeta-Jones sometimes say things that surprise even their better half.
Mistake #21: Never talk about the ex-husband in front of the current husband.
In an interview with Lucille Ball and new husband Gary Morton, Ball poignantly recalls her failed marriage to Desi Arnaz. She and Carol Matthau have a more humorous exchange on the subject of her ex-husband, William Saroyan, in front of actor Walter.
Mistake #20: You can't trust David Duchovny.
Walters warns several of her guests not to make any life-altering decisions before their interview airs, but David Duchovny did not listen. The day after he talked to Walters, he married Tea Leoni.
Mistake # 19: Never lie on a Barbara Walters' special.
Over the course of three interviews, Richard Pryor painfully recounts his history of drug use, including his lie about the fire that almost took his life.
Mistake #18: Never say anything on a Walters' special that you don't want people to remember.
Bing Crosby says, "Aloha on the steel guitar," and Sean Connery admits he has not changed the way he feels about slapping a woman in two very memorable interviews.
Mistake #17: A terrific setting isn't enough.
Walters' interview locations are always stunning, but not always functional. Try interviewing Tom Cruise with airplanes roaring in the background or Audrey Hepburn with bird droppings raining down.
Mistake #16: Never do an interview in the middle of the night, unless it's Stevie Wonder.
Drowsy eyes and tired answers were all Walters had to show for her late-night interview with Mel Gibson in 1990. But talking and singing with Stevie Wonder at 2 a.m. was an entirely different story.