Continuity mistake: While Harry is communicating with Riddle's diary, after the words "let me take you back fifty years ago" appear on the page, the ink pot's lid is open as the diary pages flip and Harry lifts the book, but in the shot from Harry's POV we see the ink pot lid closed, then the lid is open again when Harry's transported.
Continuity mistake: When Harry is in Borgin & Burkes in Knockturn Alley, he approaches the glass dome with skulls sitting on the shelf and to the right is a large round mirror sitting atop a cabinet. When he walks away after freeing his hand from The Hand of Glory, in this wide shot there is now a very tall, ornate, wrought iron fixture behind him that stands beside the shelf, in front of the round mirror and cabinet, that was not in that previous shot. (00:15:45)
Continuity mistake: When Harry escapes into the Ford Anglia, in the interior shot Ron grabs firm hold of Harry under his left arm, while Vernon pulls on Harry's foot. In the overhead exterior shot Ron's arm holds Harry above his arm, yet in the next close-up of Harry, Ron's arm is under Harry's. Then just after Ron yells, "Drive!" Ron's arm is over Harry's arm once again. (00:09:45)
Visible crew/equipment: When Harry and Ron are under the invisibility cloak in Hagrid's hut, Hagrid, Dumbledore and Fudge are joined by Lucius Malfoy. In the wide shot as Malfoy steps in, all the mats - their marks - are visible under Malfoy, Fudge and Dumbledore. Then later Dumbledore says, "If the governors desire my removal, I will of course.." and in the shot facing Malfoy as he finishes, "..step aside," the mat that Malfoy now stands on is visible as is the blue mark behind his feet. It's also visible in an earlier shot after he announces the order of suspension. The mat at the foot of Hagrid's chair disappears as well. (Visible on fullscreen DVD.) (01:39:35 - 01:40:55)
Visible crew/equipment: When Harry, Ron and Lockhart are in the girls' lavatory, Harry speaks Parseltongue to open the Chamber. Lockhart then tries to escape so the boys push him back. In this shot the white strips taped to the small black mat, which itself is taped to the floor for Rupert's mark, are plainly visible at his feet. (01:59:20)
Visible crew/equipment: After Harry says, "Rictusempra!" Malfoy is thrown across the room and lands at Snape's feet. Snape grabs Malfoy at the back of his neck and as he pulls him up, Alan Rickman's mark, the green tape, is visible at his feet, as well as Tom Felton's white tape mark at his left foot. Whereas in the earlier shot, when Snape suggests someone from his own house and says, "Malfoy, perhaps," the end of the mat is visibly without any marks. (Not visible in DVD widescreen format) (01:06:25 - 01:07:40)
Visible crew/equipment: While Harry is in Dumbledore's study, in the two semi-overhead shots as Lucius Malfoy says, "So it's true. You have returned," and later when he says, "Come Dobby, we're leaving," sitting on the floor directly behind Dumbledore is a large STEEL piece of the crew's equipment, plus in the second shot another piece of equipment actually moves in front of the steel piece. (02:21:35 - 02:23:35)
Continuity mistake: As Harry chases the Snitch after his arm is broken, he reaches and catches it in the shot facing him. In the next side shot, as he begins to roll over while still balancing on top his broom, the attached foot rest is visible between his thighs. However, when he rolls under his broom then skids to the ground, it is clear that the foot rest is gone. Whether the foot rest is in the open or closed position, it would still be visible either above or below his leg. (00:57:20)
Continuity mistake: After Harry has caught the Snitch and is sitting up, Hermione runs over to him and kneels in the sand next to him. Her robes are covering her knees in a long shot, but as it cuts to a close up her knees can be seen, and this continues to switch for the next couple of shots. (00:57:55)
Continuity mistake: The cork board, hanging over Harry's bed in the Dursley house, significantly changes its position on the wall, as seen when Harry sits on his bed to speak with Dobby. The location of the thumbtack pushed into the top point of the Gryffindor pennant, as well as the angle of the other point, also change throughout the scenes in Harry's bedroom. (00:03:10 - 00:04:45)
Continuity mistake: In the Whomping Willow, the trunk of the car recieves a noticeable gash just above the lock on the trunk as well as a huge dent in the trunk. However just before the trunk pops open to eject Harry and Ron's belongings, it is blatantly apparent that it is not the same car trunk. The gash and dent are both gone, the Ford Anglia nameplate on the right side is gone, the lock is different, the area under the bent fender is different, etc. After the spider escape, though the nameplate is back, the dent and gash are still gone. (00:27:25)
Continuity mistake: As Harry chases Dobby into the hallway, he lands behind Dobby with knees bent, his left hand and foot in front and his right hand and foot in back. The next shot he has not moved, but his stance is the opposite, left hand and foot in back and his right hand and foot in front. (00:06:55)
Revealing mistake: When Harry is looking at the photo album Hagrid gave him in his bedroom, there is a clear reflection of the photos in the lenses of his glasses. A moment later in that scene, there is no reflection seen in the lenses, because there are no actual lenses in the frames. (00:01:00)
Continuity mistake: The sun as shown in the introduction is visible and rather bright slightly above the horizon. As the shot moves through the clouds (takes only a second or two) and focuses on the houses, the sun is now shielded by clouds and is moved down quite a bit. (00:00:35)
Continuity mistake: Dumbledore asks, "Why then did the Sorting Hat place you in Gryffindor?" and in this close-up the Sorting Hat sits on two books. In the next shot, as Harry answers, "Because I asked it to." The hat now sits on three books in this close-up. During this entire scene in Dumbledore's study, things including the Sorting Hat and lamp behind Dumbledore to his right, change position depending on camera angle. (02:18:00 - 02:20:20)
Continuity mistake: In the scene where Harry is stabbing Tom Riddle's diary for the last time, he closes the book and we see a close up of its cover, covered in ink. In the next close-up of the diary its cover is clean, and a small blue dot (where the ink subsequently squirts from) is visible in the centre for Harry to aim the tooth at. (02:15:45)
Continuity mistake: When Dobby stands on Harry's desk, in the close-up he slams the lamp base into his head with the electrical cord coming out of the base to his right. Yet in the next close-up the cord comes out of the base directly in front of Dobby and is now wrapped around Dobby's neck. (00:05:25)
Continuity mistake: While in the Whomping Willow, the center point of the cracks and spider cracks around it on the car's windshield changes shape and position. In the first shot of the windshield being smashed to four shots later of Harry turning towards the back, with the windshield visible behind him. Regardless of whether more damage occurs to the windshield, the center point of each of the two cracks should be in the same place, which it is not. (00:27:15)
Continuity mistake: In the hospital wing, as Madame Pomfrey removes the skull bottle top of the Skele-Gro and sets it down, she says, "But it'll be painful," and Harry actually smirks at her. In the next close-up, as she pours some Skele-Gro into a glass and places the bottle down, the skull top now faces the opposite way. In the following shot as she hands Harry the glass, the position of both the skull top and the bottle of Skele-Gro are quite obviously different than the previous close-up. (00:58:55)
Visible crew/equipment: When Uncle Vernon falls out of Harry's window, in the interior shot as he yells, "No, no, no, no, no!" leg pads are visible under Vernon's pajamas as his legs fly out the window. (00:10:00)
Answer: The joke goes like this, "A California business man, while in Japan for some business meetings and a few rounds of golf, arrived in Tokyo a day earlier than expected. Feeling lonely that evening, he employed the services of a beautiful young Japanese girl to be his companion for the evening. Although the Japanese girl spoke very little English and the businessman spoke no Japanese, their passion roared and in the heat of the moment she began yelling "Machigatta ana. Machigatta ana" Hearing this, the Californian believed he had pleased his female Japanese friend and soon afterwards went to sleep. The next day while playing golf with his Japanese business colleague, his Japanese partner holed his shot from 170 yards away. Wanting to impress his friend, the Californian began yelling, "Machigatta ana!" The Japanese business man turned to the Californian and with a confused look on his face asked, "What do you mean wrong hole?"