History AdaptationInducedPlotHole / HarryPotter

** The first two movies rename the Forbidden Forest from the books to the Dark Forest but here they call it the Forbidden Forest. [[LuckyTranslation This was surprisingly averted in the Latin American Spanish dub]], where the name Forbidden Forest was used since the first movie.

** The first two movies rename the Forbidden Forest from the books to the Dark Forest but here they call it the Forbidden Forest.

** A minor one in the movie comes during the flying lesson. In the book, Madam Hooch tells the students to start flying on the count of three; Neville, who's terrified of flying, accidentally jumps into the air on "two". In the movie, they're supposed to start flying when Madam Hooch blows her whistle, but when she does, Neville is the only one to start flying and everyone starts telling him to come down immediately; it is played that Madam Hooch only expects them to hover and Neville immediately goes above and beyond, clearly not in control.

** The fifth film made a few changes to the events immediately following the Dementor attack. In the book, Harry's notice of expulsion also informed him that the Ministry would soon send someone to snap his wand; this was followed by further letters from both Sirius and Mr. Weasley, telling him they had postponed his expulsion and not to leave the Dursleys' house under any circumstances. Meanwhile, the film only includes the first letter from the Ministry and makes no mention of Harry's wand being snapped. This can make movie-goers wonder why he didn't bother taking his things and running away once the Dursleys had left, like he attempted to in the third installment.

* ''[[Literature/HarryPotterAndThePhilosophersStone Philosopher's Stone]]'':

* ''[[Literature/HarryPotterAndTheChamberOfSecrets Chamber of Secrets]]'':

*** Related to the Elder Wand, the film adaptation has Voldemort repeatedly claim the wand isn't serving him properly, yet he [[spoiler:has no problem killing Snape and later Pius Thicknesse with it, not even needing to specify which spell he used in the former instance.]]

** In the Gryffindor/Hufflepuff Quidditch match, Cedric Diggory is struck by lightning and falls out of the sky. Soon after, Harry also falls off his broom when the Dementors appear. Wood in the first movie already said that if Harry (as seeker) catches the golden snitch, the game is over, so how did the game end? Did Cedric get better? Did they just call the game after Harry fell? In the book, there was no lightning strike, and Harry later learns that Cedric caught the Snitch immediately after Harry fell.

** In Part 1, Mundungus was said to have dissaperated which led to Moody's death. This was because in the book, Mundungus was riding on the same broom as Moody, but in this movie, Moody could be seen alone on his broom.

** In [[Literature/HarryPotterAndThePrisonerOfAzkaban the book]] (and the video game), after Harry falls off his broom in the Quidditch match against Hufflepuff, he sees a black dog that he believes to be the Grim watching him from some empty seats. In the film, Harry inexplicably instead sees the outlines of the Grim appear in the clouds. This would theoretically make sense if the Grim he had been spotting before was really a mystical omen of death and not [[spoiler:the Animagus form of Sirius Black, as we later find out]].

** In [[Literature/HarryPotterAndThePrisonerOfAzkaban the book]] (and the video game), after Harry falls off his broom in the Quidditch match against Hufflepuff, he sees a black dog that he believes to be the Grim watching him from some empty seats. In the film, Harry inexplicably instead sees the outlines of the Grim appear in the sky. This would theoretically make sense if the Grim he had been spotting before was really a mystical omen of death and not [[spoiler:the Animagus form of Sirius Black, as we later find out]].

** The very beginning of the book has Harry, the Weasleys, and a whole bunch of other wizards and witches attending the Quidditch World Cup. After Ireland wins, there are large amounts of drunken celebrations. Some of those celebrating were former disciples of Voldemort, who levitated the muggle owners of the campsite for fun. Barty Crouch Jr., who is still a loyal disciple, gets angry, steals Harry's wand and casts the Dark Mark (while pinning it on his father's house elf, Winky) into the air as a reminder to the former Death Eaters about their true master, causing them to flee. This admittedly is a bit of a complicated setup, but the film simply has the fully costumed Death Eaters ''attacking'' the Quidditch World Cup and Crouch Jr. casting the Mark after the riots are seemingly over. No explanation is given why everyone flees in terror without trying to fight back against this small, obvious group, nor why no one believes Harry about Voldemort's return later despite the fact that Voldemort's minions have obviously returned to cause trouble.

** The very beginning of the book has Harry, the Weasleys, and a whole bunch of other wizards and witches attending the Quidditch World Cup. After Ireland wins, there are large amounts of drunken celebrations. Some of those celebrating were former disciples of Voldemort. Barty Crouch Jr., who is still a loyal disciple, gets angry, steals Harry's wand and casts the Dark Mark (while pinning it on his father's house elf, Winky) into the air as a reminder to the former Death Eaters about their true master. Chaos ensues. This admittedly is a bit of a complicated setup, but the film simply has Crouch Jr. and a bunch of other Death Eaters casting the Mark, and ''attacking'' the Quidditch World Cup. No explanation is given why everyone flees in terror without trying to fight back against this small, obvious group, nor why no one believes Harry about Voldemort's return later despite the fact that Voldemort's minions have obviously returned to cause trouble.

** The Ministry of Magic does not send a letter to the Dursley's house warning Harry for the apparent violation of the Decree for the Reasonable Restriction of Underage Sorcery after Dobby levitates and drops Petunia's pudding, which is how the Dursleys knew of this rule in the books. How Vernon seems to know of this rule in the following movie, despite noticeably not being aware in this one, is not explained [[note]]While Petunia might know of this, she does not appear to know of it in this movie, and says nothing about it to Harry or her husband when it would be relevant[[/note]].

** The "Snape's Grudge" scene is a bit weird in the film. Snape catches Harry out of his dorm at night, which is enough to get him in trouble by itself. There's no reason for Snape to suspect the map is anything but a blank piece of parchment.[[note]]Yes, Snape's a talented Legilimens, but again, Harry should be in trouble already; Snape doesn't need to look for more.[[/note]] After Lupin confiscates the Map, Harry somehow avoids further trouble. In the "Snape's Grudge" scene in the book, Snape catches Harry coming back from Hogsmeade, and has him empty his pockets and tries to reveal the Map's secret to prove Harry's been in Hogsmeade; when he can't, Harry barely escapes trouble.

** The fifth film made a few changes to the events immediately following the dementor attack. In the book, Harry's notice of expulsion also informed him that the Ministry would soon send someone to snap his wand; this was followed by further letters from both Sirius and Mr. Weasley, telling him they had postponed his expulsion and not to leave the Dursleys' house under any circumstances. Meanwhile, the film only includes the first letter from the Ministry and makes no mention of Harry's wand being snapped. This can make movie-goers wonder why he didn't bother taking his things and running away once the Dursleys had left, like he attempted to in the third installment.

** In [[Literature/HarryPotterAndTheGobletOfFire the fourth book]], Barty Crouch, Jr. had infiltrated Hogwarts and manipulated things so that Harry would fall into the hands of Voldemort, which allowed for the latter's return. After he confessed everything to Dumbledore, Fudge was informed about the culprit and decided to have a Dementor accompany him -- the Dementor saw Crouch Jr. and [[FateWorseThanDeath gave him the Dementor's Kiss]], which left him no longer be able to give testimony anymore, and nobody to verify Harry's story of Voldemort's return. The movie removed this side-effect by stating Crouch Jr. has been taken back to Azkaban, but is otherwise perfectly alright. The media still portrays Harry (and, to an extent, Dumbledore) as liars based on nothing but bad propaganda. This also raises the question of why Barty Jr. isn't freed during the mass Azkaban breakout.

** In [[Literature/HarryPotterAndTheGobletOfFire the fourth book]], Barty Crouch, Jr. had infiltrated Hogwarts and manipulated things so that Harry would fall into the hands of Voldemort, which allowed for the latter's return. After he confessed everything to Dumbledore, Fudge was informed about the culprit and decided to have a Dementor accompany him -- the Dementor saw Crouch Jr. and [[FateWorseThanDeath gave him the Dementor's Kiss]], which left him to no longer be able to give testimony anymore, and nobody to verify Harry's story of Voldemort's return. The movie removed this side-effect by stating Crouch Jr. has been taken back to Azkaban, but is otherwise perfectly alright. The media still portrays Harry (and, to an extent, Dumbledore) as liars based on nothing but bad propaganda. This also raises the question of why Barty Jr. isn't freed during the mass Azkaban breakout.

** In [[Literature/HarryPotterAndTheGobletOfFire the fourth book]], Barty Crouch, Jr. had infiltrated Hogwarts and manipulated things so that Harry would fall into the hands of Voldemort, which allowed for the latter's return. After confessing everything to Dumbledore, Fudge was informed about the culprit and decided to have a Dementor accompany him -- the Dementor saw Crouch Jr. and [[FateWorseThanDeath gave him the Dementor's Kiss]], which left him to no longer be able to give testimony anymore, and nobody to verify Harry's story of Voldemort's return. The movie removed this side-effect by stating Crouch Jr. has been taken back to Azkaban, but is otherwise perfectly alright. The media still portrays Harry (and, to an extent, Dumbledore) as liars based on nothing but bad propaganda. This also raises the question of why Barty Jr. isn't freed during the mass Azkaban breakout.

** In [[Literature/HarryPotterAndTheGobletOfFire the fourth book]], Barty Crouch, Jr. had infiltrated Hogwarts and manipulated things so that Harry would fall into the hands of Voldemort, which allowed for the latter's return. After confessing everything to Dumbledore, Fudge was informed about the culprit, who decided to have a Dementor accompany him -- the Dementor saw Crouch Jr. and [[FateWorseThanDeath gave him the Dementor's Kiss]], which left him to no longer be able to give testimony anymore, and nobody to verify Harry's story of Voldemort's return. The movie removed this side-effect by stating Crouch Jr. has been taken back to Azkaban, but is otherwise perfectly alright. The media still portrays Harry (and, to an extent, Dumbledore) as liars based on nothing but bad propaganda. This also raises the question of why Barty Jr. isn't freed during the mass Azkaban breakout.

** In [[Literature/HarryPotterAndTheGobletOfFire the fourth book]], Barty Crouch, Jr. had infiltrated Hogwarts and manipulated things so that Harry would fall into the hands of Voldemort, which allowed for the latter's return. After confessing everything to Dumbledore, Fudge was informed about the culprit, who decided to have a Dementor accompany him -- the Dementor saw Crouch Jr. and [[FateWorseThanDeath gave him the Dementor's Kiss]], which left him to no longer be able to give testimony anymore, and nobody to verify Harry's story of Voldemort's return. The movie removed this side-effect by stating Crouch Jr. has been taken back to Azkaban, but is otherwise perfectly alright. The media still portrays Harry (and, to an extent, Dumbledore) as liars based on nothing but bad propaganda.

** In the Gryffindor/Hufflepuff Quiddich match, Cedric Diggory is struck by lightning and falls out of the sky. Soon after, Harry also falls off his broom when the Dementors appear. Wood in the first movie already said that if Harry (as seeker) catches the golden snitch, the game is over, so how did the game end? Did Cedric get better? Did they just call the game after Harry fell?

** In [[Literature/HarryPotterAndTheGobletOfFire the fourth book]], [[spoiler:Barty Crouch, Jr]] had infiltrated Hogwarts and manipulated things so that Harry would fall into the hands of Voldemort, which allowed for the latter's return. After confessing everything to Dumbledore, Fudge was informed about the culprit, who decided to have a Dementor accompany him -- the Dementor saw Crouch Jr. and [[FateWorseThanDeath gave him the Dementor's Kiss]], which left him to no longer be able to give testimony anymore, and nobody to verify Harry's story of Voldemort's return. The movie removed this side-effect by stating Crouch Jr. has been taken back to Azkaban, but is otherwise perfectly alright. The media still portrays Harry (and, to an extent, Dumbledore) as liars based on nothing but bad propaganda.

** In the [=GameCube/PS2=]/Xbox version, the third chapter of Gilderoy Lockhart's book "Marauding with Monsters" contains a CriticalResearchFailure regarding the Diricawl (he calls it by its {{Muggle}} name and believes it is extinct) and ends with him declaring an intent to assist poachers in driving a known EndangeredSpecies to extinction. This is ostensibly supposed to foreshadow Lockhart's true nature as a fraud, but it's [[ViewersAreMorons so utterly blatant]] it makes everyone in-universe look like complete idiots. Are we seriously expected to believe that a supposedly world famous professor is both as knowledgeable as a {{Muggle}} about the Diricawl and an admitted ''criminal'' yet nobody noticed or cared?

** In [[Literature/HarryPotterAndTheGobletOfFire the fourth book]], [[spoiler:Barty Crouch, Jr]] had infiltrated Hogwarts and manipulated things so that Harry would fall into the hands of Voldemort, which allowed for the latter's return. After confessing everything to Dumbledore, Fudge was informed about the culprit, who decided to have a Dementor accompany him -- the Dementor saw Crouch Jr. and [[AFateWorseThanDeath gave him the Dementor's Kiss]], which left him to no longer be able to give testimony anymore, and nobody to verify Harry's story of Voldemort's return. The movie removed this side-effect by stating Crouch Jr. has been taken back to Azkaban, but is otherwise perfectly alright. The media still portrays Harry (and, to an extent, Dumbledore) as liars based on nothing but bad propaganda.

** [[AvertedTrope Averted]] by pure luck in the UsefulNotes/GameBoyColor version, which has Harry stab Riddle's diary with the Sword of Gryffindor instead of a basilisk fang. As ''Deadly Hallows'' would later reveal, the sword can indeed destroy horcruxes after being coated in basilisk venom.