Former Manchester United midfielder Scholes was often critical of Mouirnho during the Portuguese manager's time at Old Trafford while working as a TV pundit.
There were concerns that his 10% stake in Salford City, the National League club he co-owns, would prevent him from taking charge of the Latics.
The 44-year-old had been reported as the new manager of the club over the weekend but has now been confirmed.
He said: "If I go into coaching or management and results are not good, I have left myself open to a bit of stick but I am big enough to take it".
"I wanted to come into this with my full coaching badges and I've got them now".
"If we are losing I am sure people will be popping up", he stated.
"I have never really understood why players and managers take notice of what pundits say anyway".
"It wasn't something I was quite ready to do and there's obviously been three or four times over the last six years where it could have happened and I've not been quite ready".
Scholes subsequently follows in the footsteps of former teammates Ryan Giggs, Phil Neville, Gary Neville, and Roy Keane who have either previously/or-are-currently dabbling in the chaotic world of football management.
He will take charge of his first match against Yeovil at Oldham's Boundary Park ground on Tuesday.
There have been reports of interference in team affairs from club owner Abdallah Lemsagam and his brother Mohamed - the club's sporting director - but Scholes is adamant he will not accept that.