Winfrey said her immediate reaction to the tweet from Trump was confusion.
"I don't like giving negativity power, so I just thought 'What?'" she told Ellen DeGeneres in a segment that airs today on her talk show. "What I actually really did was I went and looked back at the tape to see if there was any place that could be true."
In her report, Oprah moderated a discussion that included an equal mix of Trump supporters and critics from Michigan, a key state he narrowly won on his way to the presidency.
"I went back and looked at every tape, I called the producer," she continued. "When you do '60 Minutes,' you sit in a room with at least seven other people who critique the piece before you air it ... you have a whole panel of people looking at it, whether it was fair."
In fact, the veteran journalist said after first seeing the rough cut of the piece, she felt it was missing a voice from a Trump supporter on what people think about America. So, they made sure to add that in to make it more balanced.
"So, I was working hard to do the opposite of what I was hate-tweeted about," she said.
In the tweet Oprah was referring to, Trump also called the media mogul "very insecure," while adding, "the facts incorrect. Hope Oprah runs so she can be exposed and defeated just like all of the others!"
Winfrey appeared on "Jimmy Kimmel Live!" Thursday night and said she has no problems with insecurity. Kimmel asked if she'd ever felt insecure in the last 35 years.
"I'm trying to think about -- have I ever?" she said. "Trying to think when that would be."
She added that she never once thought about tweeting a response to Trump.
Although Trump resurfaced the idea of Oprah running for President in 2020, which took off in internet reactions to her passionate Golden Globes speech about gender and racial inequality earlier this year, she has said that isn't her plan.
Winfrey reiterated to Kimmel that she has no plans to run for president.
"I am definitely not running," Winfrey said, after turning to look straight into the camera.
"I’ve always felt very secure and confident with myself in knowing what I could do and what I could not," she told InStyle at the end of January about running for office. "And so it’s not something that interests me. I don’t have the DNA for it."