The talk show host, who recently laid off 30 staffers at the 15-month-old network after poor ratings, told "CBS This Morning" that she had been ill-prepared for the venture.

"The idea of creating a network was something that I'd wanted to do, had I'd known that it was this difficult, I might have done something else," she told the morning program co-hosted by her longtime close friend Gayle King.

Winfrey, 58, had appeared unstoppable in her career with a 25-year reign on "The Oprah Winfrey Show," but when questioned about whether she seriously would have never taken on the project, she replied, "Oh absolutely."

"I did not think it was going to be easy ... but if I knew then what I know now I might have made some different choices. I would say if I was writing a book about it, I could call the book '101 mistakes.'"

Within the top five mistakes?

"Launching when we really were not ready to launch," she said. "It's like having the wedding when you know you are not ready and you are walking down the aisle, and you are saying, 'I don't know ... maybe we should have postponed it.'"

Now she realizes she should have waited to launch the network until she finished her duties hosting "The Oprah Winfrey Show," which ended in May 2011.

OWN, a joint venture between Winfrey and Discovery Communications, has struggled to find a sizeable audience since its launch in January 2011.

But Winfrey defended herself saying she had initially warned partner Discovery that "the thing that I am most worried about is who is going to lead this train, because I can't do it."

Now, she said, such is her commitment to the network that she will not be available to campaign for President Barack Obama in his re-election bid in a step back from her influential campaigning for Obama in late 2007.

"I am not going to be out there. I am 100 per cent behind our president. I actually love our president and have the utmost respect for him and that office and what it takes to be there. I will not be out because I am trying to fix the network," she said.

OWN saw a 21 percent rise in total daily viewers in the first quarter of 2012 after Winfrey appeared more on the channel. But it is still attracting only 180,000 viewers a day.

In March the network laid off 30 production staffers and canceled comedian Rosie O'Donnell's talk show after just five months due to sagging ratings.

Winfrey admitted that along with the layoffs, the bad press about the channel's struggles had hurt but later added that she felt better about her network OWN today than she ever has.

"Our strategy is to do what we should have done at the beginning and that is to build one show, one hour, one night at a time and then move to the next night," she said.

Lately Winfrey boosted primetime ratings with high-profile interviews including Whitney Houston's family, Lady Gaga, rocker Steven Tyler and mega-church pastor Joel Osteen.

When asked if audiences would see more of her, she replied, "I said from the beginning, this channel can't be based upon me, it has to be based upon my philosophy, my ideas" and vowed not to end the network or her general life aims.

"I believe that I am here to fulfill a calling, that because I am a female who is African American who has been so blessed in the world, there is never going to be a time to quit," she said.

The channel's inspirational tone will still fit in with its early aims as a TV version of her "O" magazine, she said.

"I will die in the midst of doing what I love to do and that is using my voice and using my life to try to inspire other people to live the best of theirs."

(Editing by Patricia Reaney and Jill Serjeant)

• A Permanent Economic Emergency