The 2016 'X Factor' team also posed for the first official pictures of this year's judging line-up before the try-outs in Leicester at the King Power Stadium.
They will now hold auditions across the country, hoping to unearth the newest singing talent.
Simon rehired his former colleagues in the hope of improving on last year's lacklustre 12th series, which struggled in the ratings.
Nicole, who starred on both the 2012 and 2013 series, added: “I can’t wait to be back in the UK and on the show with the best judges sitting alongside me on the panel."
After being ditched for Radio 1 DJ Grimmy last year, Louis was also pleased to have his old seat back.
“He’d say otherwise but I knew Simon missed me last year!" he said.
'The X Factor' returns to ITV in the autumn. See more pictures from the first day of auditions below...
'X Factor' 2016 Auditions Begin
(01 of11)
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LEICESTER, ENGLAND - JUNE 10: Nicole Scherzinger arrives for the first X Factor auditions of 2016 on June 10, 2016 in Leicester, United Kingdom. (Photo by Eamonn M. McCormack/Getty Images) (credit:Eamonn M. McCormack via Getty Images)
(02 of11)
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LEICESTER, ENGLAND - JUNE 10: Dermot O'Leary arrives for the first X Factor auditions of 2016 on June 10, 2016 in Leicester, United Kingdom. (Photo by Eamonn M. McCormack/Getty Images) (credit:Eamonn M. McCormack via Getty Images)
(03 of11)
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LEICESTER, ENGLAND - JUNE 10: Simon Cowell arrives for the first X Factor auditions of 2016 on June 10, 2016 in Leicester, United Kingdom. (Photo by Eamonn M. McCormack/Getty Images) (credit:Eamonn M. McCormack via Getty Images)
(04 of11)
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LEICESTER, ENGLAND - JUNE 10: Louis Walsh arrives for the first X Factor auditions of 2016 on June 10, 2016 in Leicester, United Kingdom. (Photo by Eamonn M. McCormack/Getty Images) (credit:Eamonn M. McCormack via Getty Images)
(05 of11)
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LEICESTER, ENGLAND - JUNE 10: Nicole Scherzinger arrives for the first X Factor auditions of 2016 on June 10, 2016 in Leicester, United Kingdom. (Photo by Eamonn M. McCormack/Getty Images) (credit:Eamonn M. McCormack via Getty Images)
(06 of11)
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LEICESTER, ENGLAND - JUNE 10: Dermot O'Leary arrives for the first X Factor auditions of 2016 on June 10, 2016 in Leicester, United Kingdom. (Photo by Eamonn M. McCormack/Getty Images) (credit:Eamonn M. McCormack via Getty Images)
(07 of11)
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'X Factor' Launch at Leicester City FC King Power StadiumFeaturing: Sharon OsbourneWhere: Leicester, United KingdomWhen: 10 Jun 2016Credit: James Watkins/WENN.com (credit:James Watkins/WENN.com)
(08 of11)
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LEICESTER, ENGLAND - JUNE 10: Louis Walsh arrives for the first X Factor auditions of 2016 on June 10, 2016 in Leicester, United Kingdom. (Photo by Eamonn M. McCormack/Getty Images) (credit:Eamonn M. McCormack via Getty Images)
(09 of11)
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Picture Shows: Sharon OsbourneJune 10, 2016Celebrity judge Sharon Osbourne arrives on the red carpet to attend the auditions for 'The X Factor' held in Manchester, England.Non ExclusiveWORLDWIDE RIGHTSPictures by : FameFlynet UK � 2016Tel : +44 (0)20 3551 5049Email : info@fameflynet.uk.com (credit:Seb / FameFlynet.uk.com)
(10 of11)
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*** MANDATORY BYLINE TO READ: Syco / Thames / Dymond *** ***MANDATORY BYLINE TO READ: Syco/Thames/Dymond***Start of filming for the 2016 X Factor. The X Factor Judges, Simon Cowell, Sharon Osbourne, Nichole Scherzinger and Louis Walsh visit Leicester's King power Stadium for the first day of the room auditions.
LEICESTER, ENGLAND - JUNE 10: Simon Cowell arrives for the first X Factor auditions of 2016 on June 10, 2016 in Leicester, United Kingdom. (Photo by Eamonn M. McCormack/Getty Images) (credit:Eamonn M. McCormack via Getty Images)