The Reds have begun the new season in dismal form, picking up nine points from their opening eight games.
Ole Gunnar Solskjaer’s side are just two points above the relegation zone in 12th place as they prepare for the visit of runaway leaders Liverpool this weekend.
United’s slump began after Sir Alex Ferguson retired in 2013, but Scholes was keen to point out that the departure of chief executive David Gill also had a negative impact on the club.
Executive vice-chairman Ed Woodward took charge of transfer business after that point and Scholes believes that some of his earliest moves were a sign of what was to come.
“When you look five or six years ago when Alex left, the other person who didn't get the credit he deserved was David Gill,” Scholes told Radio Five Live.
“He was a football man and he knew footballers. From the day he and Sir Alex left, it has been difficult.
"I think the alarm bells rang straight away when David (Moyes) took over and signed Juan Mata and Marouane Fellaini for £70m.
"They are good players but I don't think they were Man Utd players. I don't think Sir Alex and David Gill would have signed those players.
"We are in this position now because we have signed players who are not Man Utd players. Ole is in there now and trying to put it right.
When asked about what can be done to put things right, Scholes reiterated his faith in his former team-mate Solskjaer.
"I think four or five transfer windows, and they have to be good transfer windows," he said.
“Ole's first three signings have been good and promising. As long as he is in charge of the players coming in, I don't see a problem.
"We hope it goes to back challenging for titles and Champions Leagues.”
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