Tiny Virginia Makopo, pictured here in 2008, is the former dormitory matron at the Oprah Winfrey Leadership Academy for Girls. (STR/AFP/Getty)

The former dormitory matron at Oprah Winfrey's school for girls in South Africa has been acquitted of charges of abusing the teens in her care.

Tiny Virginia Makopo faced 14 charges including indecent assault and soliciting underage girls to perform indecent acts soon after the school opened in 2007.

"The magistrate indicated that the state did not prove itself case beyond reasonable doubt on all the charges. We won't be appealing the judgment," Mthunzi Mhaga, a spokesman for South Africa's National Prosecuting Authority, said Monday

Winfrey reacted by saying she was disappointed by the result.

"I will forever be proud of the nine girls who testified with the courage and conviction to be heard," the media mogul and talk show host said in a statement Monday.

Winfrey, who herself suffered from sexual abuse as a child, promised to overhaul the Oprah Winfrey Leadership Academy for Girls located outside Johannesburg. The 8.9-hectare campus is home to about 300 girls.

Winfrey also said the school's staff "is committed to providing a nurturing educational environment so that all of our girls may continue to flourish. And they are indeed thriving."

In March, the Chicago-based media star settled a defamation lawsuit filed in Philadelphia by the school's former headmistress, Nomvuyo Mzamane, who claimed Winfrey defamed her in remarks made in the wake of the sex-abuse scandal.

Mzamane claimed that she was never told of any sexual abuse and had trouble finding a job as a result of Winfrey's remarks about her.

With files from The Associated Press