Carolynne returned during the ninth series of the show in 2012, singing "Clown" as sung by Emeli Sande during her first audition, which allowed her to progress through to the Bootcamp stages of the series.
During this stage she sung "Moves like Jagger" by Maroon 5 as part of a group, and advancing to the next day of Boot camp.
Carolynne initially auditioned for the X Factor in the 2011 series of the show, where she managed to reach the judges houses stage of the competition, being mentored under Louis Walsh.
However she was eliminated at this stage and didn't advance in the competition.
Clark, who received death threats over Twitter last week, performed Spandau Ballet's Gold last night while wearing a gold vest and surrounded by Cleopatra dancers.
Barlow said he was "embarrassed", and criticised the judges for keeping Clark in the competition.
She returned to the show the following series in 2012 and made it to the live shows, but was eliminated after the first live show following a sing-off against Rylan Clark.