Scholes won 20 major trophies at United under Sir Alex Ferguson, but it is safe to say he is less than impressed by the man who is currently in charge at Old Trafford.
The former England midfielder said some of United's play under the Dutchman had been "miserable" and complained that strikers Robin van Persie and Radamel Falcao looked like "strangers" in the 3-1 win against Burnley on Wednesday. Scholes also criticised Van Gaal for playing Wayne Rooney in midfield.
The 40-year-old is not the only person to criticise United of late.
Falcao's agent Jorge Mendes said United would not be struggling if Ferguson was in charge, Sam Allardyce branded Van Gaal's team "long-ball United" and even veteran Preston striker Kevin Davies mocked the former Bayern Munich coach ahead of Monday's FA Cup tie with the Red Devils at Deepdale, claiming the squad looked unhappy.
"I don't worry about it, it's not so interesting I think because he (Scholes) is one of the fans, I hope, and he can criticise," the United boss said.
"Fans can criticise, and that's not a problem.
"I am used to it and I think all the players are used to it because they are professional football players.
"Maybe some players are affected, but normally most of the time it does not affect me or the players."
Although United returned to winning ways this week after the drab draw at West Ham last Sunday, a few fans made their displeasure at the team's style of play known by whistling at the players in the first half on Wednesday.
Van Gaal admitted he was concerned about the negativity from the supporters and he hopes to bring a smile back to their faces by recording a comprehensive win at League One Preston.
"I was disappointed we played that way," Van Gaal said.
"Nowadays the result is very important but I think the playing style is also important because you play for the fans. Manchester United has a lot of fans, so you have to play for them.
"Next match we can show that we are still in our process and positive."
The first signs of unrest came last month at QPR when United fans demanded Van Gaal ditch his three-man defence by chanting "4-4-2".
The 63-year-old has acquiesced to their demands in recent weeks, altering the formation to a 4-4-2 diamond, but he concedes - eight months into the job - that he still does not know they best way to line up his United team.
"No, I don't think so," Van Gaal said when asked if he had found the right balance in his starting XI.
"I have played five or six systems and I am looking still for the balance. But this system is more attractive than normally and I can play with more attacking players.
"That's the reason I am doing that.
"In spite of the fact that we are looking for the balance, our results are not bad and our defensive organisation is not bad, we also score a lot of goals. So, I cannot say that I am very disappointed about that. But we have to do it now, and normally you have to do it pre-season."
Van Persie is a doubt for Monday's match because of an unspecified injury, Van Gaal revealed.
The knee injury Phil Jones suffered against Burnley is not as bad as first feared, but he is unlikely to play at Preston.
Daley Blind, who came off in the first half against Burnley after a clash of heads, is more likely to play, though.
Van Gaal reported some bad news regarding Michael Carrick, who has suffered a setback in his recovery from the calf injury he suffered at the end of last month.
Carrick was supposed to be out for four weeks, but his lay-off could last longer.
"He has a setback," Van Gaal said on MUTV.
"That's not unusual with injuries so we will also have to wait and see."
- More about:
- Manchester United