Born in Halifax, West Yorkshire, Kenny began his career with Bradford Park Avenue before turning professional in the summer of 1998 upon signing for Neil Warnock's Bury.
Kenny would later sign for Warnock once again in 2010, joining Queens Park Rangers after his time at Sheffield United ended on a sour note when he spent much of his final season on the sidelines having failing a drugs test the previous summer.
He stayed at Leeds for two years, before brief spells with Bolton Wanderers, Oldham Athletic (on loan), Ipswich Town, Bury, and Rotherham United.
[3] With Dean Kiely in goal for the "Shakers", Kenny was loaned out to Whitby Town in the Northern Premier League to gain some first team experience in March 1999.
[13] Kenny began to voice disquiet over his contract situation at the end of 2008,[14] despite manager Kevin Blackwell insisting that the club were set to open talks on a new deal.
[17] He returned to the first team after sitting out two league games and was again ever present until the end of the 2008–09 season, including an appearance at Wembley Stadium in the Championship play-off final.
[3] Despite an unsuccessful appeal against his ban, Sheffield United still opted to agree a new contract extension with Kenny during his enforced absence from first team football.
[24] Kenny continued to remain Rangers number one keeper in their first season back in the Premier League, making 33 starts and keeping seven clean sheets.
QPR retained their Premier League place on the final day of the 2011–12 season, despite Kenny conceding an injury time goal to Sergio Agüero to lose the title deciding game against Manchester City.
The texts were reported to have mocked the club's poor first result of the season and, in particular, the performance of Green; Kenny subsequently had his Twitter account deleted.
[28] Kenny signed for Leeds United on a three-year contract in July 2012, linking up with manager Neil Warnock for a fourth time in his career.
On 22 February 2014, Kenny missed his first league game since signing for Leeds, due to an ongoing injury he picked up against Nottingham Forest earlier in the 2013–14 season.
Leeds signed Jack Butland on loan who went straight into the first team and made his debut in a 0–0 draw with Middlesbrough, where he received the man of the match award.
[35] On 3 July, the Professional Footballers' Association investigated alleged media reports that Kenny had been dropped due to his birthdate falling on the 17th of a month,[36] with owner Massimo Cellino having a deep superstition of the number 17.
[41] Kenny signed for Bolton Wanderers on a short-term deal on 19 September 2014 to provide competition for Andy Lonergan after Ádám Bogdán was ruled out with injury.
[42] After just two months at the Macron Stadium operating solely as an unused substitute, Kenny was loaned out to Oldham Athletic after manager Lee Johnson lost faith in Paul Rachubka.
[43] He played four matches in all competitions for Oldham – his last game for the club was a 7–0 defeat by Milton Keynes Dons,[44] in what turned out to be his final appearance in professional football.
[57] He was called up by manager Brian Kerr and made his debut in 2004 as late substitute in a 2–1 win against the Czech Republic, before going on to make his first start in a 1–0 friendly victory over Jamaica.
[58] Kenny won seven caps before deciding to retire from international football in 2007, asking then manager Steve Staunton not to consider him for selection to allow him to sort out personal issues.
[60][61] In October 2023, Kenny was appointed joint-manager of Northern Counties East League Premier Division club Goole alongside Nathan Helliwell.