Touching the net with any part of the body while the ball is in play.
When blocking a ball coming from the opponent’s court, it’s illegal to contact the ball when reaching over the net if both your opponent has not used 3 contacts and they have a player there to make a play on the ball.
When attacking a ball coming from the opponent’s court, contacting the ball when reaching over the net is a violation if the ball has not yet broken the vertical plane of the net.
Crossing the court centerline with any part of your body is a violation. Exception: if it is the hand or foot. In this case, the entire hand or entire foot must cross for it to be a violation.
Serving out of rotation/order.
Back-row player blocking (deflecting a ball coming from the opponent) when, at the moment of contact, the back-row player is near the net and has part of his/her body above the top of the net. This is an illegal block
Back-row player attacking a ball inside the front zone (the area inside the 3M/10-foot line) when, at the moment of contact, the ball is completely above the net. This is an illegal attack.