They have never.
Manchester United won the Carling Cup in 2003, 2009, and 2010.
Manchester united have won it 2 times in a row 2007-2008 and 2008-2009
They're strong favourites. And given the trouble Spurs had in putting down Burnley, they've every right to be.
Manchester united win fortyeight cup over all
Manchester United have won the Premier League 12 times.
Manchester United
Manchester United.
As Manchester United is a club and not a country it can not win any world cups at all.
Eleven
85
19 times
3