Vidic left United this summer having amassed 15 trophies during his eight years at the club.
His final season at Old Trafford proved to be a trophyless and joyless experience for the Serb, though.
Under David Moyes’ stewardship, United ended the campaign in seventh position — their worst finish in the Premier League era.
But with former Barcelona and Bayern Munich manager Van Gaal now at the helm, Vidic thinks things are looking up for United.
“Van Gaal has a lot of experience, he has trained a lot of teams in a lot of leagues and that shows he knows what he is doing,” the new Inter Milan centre-back said after playing United in a friendly on Tuesday night.
“I believe he can do good work and the players think the same.”