History AdaptationInducedPlotHole / HarryPotter

** Averted by Creator/JKRowling herself, who stepped in after learning the fifth film would be cutting out the character Kreacher, and warned the crew that adapting [[Literature/HarryPotterAndTheDeathlyHallows book seven]] would be very problematic if he hadn't appeared before. However, so much of him was cut from ''Deathly Hallows Part 1'', and he was completely absent from ''Part 2'', that they might as well have removed him entirely.

** Every version completely glosses over Harry's [[ConvenientlyAnOrphan backstory]] with a vague mention of "Harry Potter...the boy who lived", possibly because talking about how Harry's parents were murdered by the BigBad would [[UsefulNotes/MediaClassifications bump up the age rating]]. [[note]]Or possibly because anyone who would play that game already knows Harry's backstory, and EA didn't want the prologue to take too long.[[/note]]

** In the [[UsefulNotes/TheSixthGenerationOfConsoleVideoGames GameCube/PS2/Xbox]] version, Harry and Hagrid never go to Gringotts or visit Vault 713, but Harry and Ron still read about the break-in and Harry talks about the vault as if he's already seen it.

** [[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 ''Deathly Hallows'' would later reveal, the sword can indeed destroy horcruxes after being coated in basilisk venom.

** The UsefulNotes/PlayStation version removes a lot of plot-relevant events, possibly due to space limitations. It is never explained that the Basilisk "kills" people by looking at them, but the scene with Fawkes blinding the snake still plays. Harry still hears the Basilisk speaking to him through the pipes, but this is never mentioned nor explained in any way. In the final battle, Harry falls unconscious due to being bitten by the Basilisk, except he was never bitten in the game, and so on.

** In the book, when Harry tries to floo from the Burrow to Diagon Alley, he coughs while saying the name of his destination. The movie changes this to him pronouncing "Diagon Alley" in an odd way with no explanation, even though the movie kept Mr. and Mrs. Weasley instructing him to speak clearly.

** 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 onscreen to Harry or her husband when it would be relevant[[/note]].

** In the novel, Hermione asks Professor Binns to tell the class about the Chamber of Secrets. Binns is the History of Magic teacher, so it is perfectly reasonable for her to ask him about something connected to the history of Hogwarts. However, Binns is absent in the film, so Hermione asks Professor [=McGonagall=] about it, which makes far less sense and is completely off-topic from the subject she teaches (Transfiguration). This can, however, be justified in that [=McGonagall=] is the deputy headmistress (and Hermione's head of house), and thus would be the most likely of the film's teachers to know about it.

*** When Lupin steps in front of the Boggart, in the book it transforms into an abstract "shining ball", leading the boys to wonder why that would be Remus' greatest fear. In the movie it becomes an unmistakably exact image of the Moon, and yet noone makes the now obvious connection.

** The Two-Way Mirror that Sirius gives to Harry in the [[Literature/HarryPotterAndTheOrderOfThePhoenix fifth book]] is left out of the film. This creates some rather glaring continuity problems further down the line for the ''[[Film/HarryPotterAndTheDeathlyHallows Deathly Hallows]]'' films. In the book, Harry ended up smashing the mirror in frustration after a failed attempt to use it to [[spoiler:contact Sirius beyond the grave]]. After this, Harry decides to save a shard of the smashed mirror as a keepsake. Meanwhile, due to [[spoiler:Sirius' death]], the other mirror ends up in the hands of Mundungus Fletcher, who ends up selling it to Dumbledore's brother, Aberforth. This leads to Harry observing a bright blue eye sometimes looking back at him from the shard, and due to the striking resemblance to Dumbledore's own eye, Harry ends up assuming that it is Dumbledore trying to [[spoiler:contact him from the afterlife]]. This is why Harry, when imprisoned in the cellar of Malfoy Manor in the [[Literature/HarryPotterAndTheDeathlyHallows seventh book]], looks at the shard and begs for help. His plea for help is heard by Aberforth, who in response alerts Dobby, who then arrives to break Harry and the gang out. In the [[Film/HarryPotterAndTheDeathlyHallows seventh film]], however, absolutely none of this context is given at any point, so to someone only familiar with the films, it comes across as Harry just suddenly and randomly taking a strange mirror shard out of his sock and begging it for help, resulting in it somehow summoning Dobby. While the second part of ''Hallows'' does make an attempt to patch over this hole -- by showing that the shard is a piece from a mirror found in Aberforth's house, and otherwise giving it a part of the book backstory of him having bought it off Fletcher -- this only makes the whole thing a minor VoodooShark, as it raises the question of why Aberforth would buy a broken mirror, and it still doesn't explain how Harry acquired the mirror shard, why he would keep the shard on his person, nor why he would feel compelled to call to it for help.

** In Part 1, Mundungus was said to have disapparated, leading 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.

** When Wood explains Quidditch to Harry, he says, "You catch [the GoldenSnitch], Potter, and we win", making it sound like an InstantWinCondition and implying the Keeper and Chaser positions are practically irrelevant. Catching the Snitch awards 150 points, so it's possible to still lose if the opposing team has a more than 150 point lead (the houses also play a round-robin schedule in the novels, so point differential is important), and while rare, this situation does indeed occur at the Quidditch World Cup in ''[[Literature/HarryPotterAndTheGobletOfFire Goblet of Fire]]'', where Viktor Krum catches the Snitch for Bulgaria, but Ireland still wins due to their superior Chasers. However, this detail ''is'' mentioned later by Lee Jordan.

** When Wood explains Quidditch to Harry, he says, "You catch [the GoldenSnitch], Potter, and we win", making it sound like an InstantWinCondition and implying the Keeper and Chaser positions are practically irrelevant. Catching the Snitch awards 150 points, so it's possible to still lose if the opposing team has a more than 150 point lead (the houses also play a round-robin schedule in the novels, so point differential is important), and while rare, this situation does indeed occur at the Quidditch World Cup in ''[[Literature/HarryPotterAndTheGobletOfFire Goblet of Fire'', where Viktor Krum catches the Snitch for Bulgaria, but Ireland still wins due to their superior Chasers. However, this detail ''is'' mentioned later by Lee Jordan.

** In Oliver Wood's film explanation of Quidditch rules to Harry, he says, "You catch [the GoldenSnitch], Potter, and we win." This makes it sound even more like an InstantWinCondition than it is. Catching the Snitch only awards 150 points and, while rare, it is still possible to lose when catching the Snitch if the opposing team has a more than 150 point lead; the houses also play a round-robin schedule in the novels, so point differential is a major factor. Wood's book explanation, "Whichever Seeker catches the Snitch wins his team an extra hundred and fifty points, so they nearly always win," makes it far more understandable why the Keeper and Chaser positions even exist (and this is further reinforced by examples like the Quidditch World Cup in ''Goblet of Fire'', where Viktor Krum catches the Snitch for Bulgaria, but Ireland wins because they have the better Chasers), while they are implied to be completely superfluous in the film. However, this detail ''is'' mentioned later on by Lee Jordan.

** In Oliver Wood's film explanation of Quidditch rules to Harry, he says, "You catch [the Golden Snitch], Potter, and we win." This makes it sound even more like an InstantWinCondition than it is. Catching the Snitch only awards 150 points and, while rare, it is still possible to lose when catching the Snitch if the opposing team has a more than 150 point lead; the houses also play a round-robin schedule in the novels, so point differential is a major factor. Wood's book explanation, "Whichever Seeker catches the Snitch wins his team an extra hundred and fifty points, so they nearly always win," makes it far more understandable why the Keeper and Chaser positions even exist (and this is further reinforced by examples like the Quidditch World Cup in ''Goblet of Fire'', where Viktor Krum catches the Snitch for Bulgaria, but Ireland wins because they have the better Chasers), while they are implied to be completely superfluous in the film. However, this detail ''is'' mentioned later on by Lee Jordan.

*** Of course, this also causes an example of the trope being PlayedStraight. In the book, before returning the Elder Wand, Harry used it to repair his own wand. In the film, he never gets around to this, leaving him apparently without a wand going forward. However, it is entirely possible that Harry either fixed his wand off-screen or continued to use Draco's wand, which answers to him.

** The films omit the entirety of Percy Weasley's minor-but-existent character arc from ''[[Literature/HarryPotterAndTheGobletOfFire Goblet of Fire]]'', ''[[Literature/HarryPotterAndTheOrderOfThePhoenix Order of the Phoenix]]'', ''[[Literature/HarryPotterAndTheHalfBloodPrince Half-Blood Prince]]'', and ''[[Literature/HarryPotterAndTheDeathlyHallows Deathly Hallows]]'', leaving it totally unexplained why he's suddenly working for [[ArcVillain Dolores Umbridge]] in the fifth movie, then just as suddenly back with the good guys in the finale.
** In the books, the reason the public believes Sirius was the first ever prisoner to escape Azkaban is because Barty Crouch Jr. had been smuggled out of Azkaban after he and his dying mother used Polyjuice Potion to assume each other's appearances, and Mrs. Crouch subsequently died bearing her son's identity. In the movie, all of Barty Crouch Sr.'s dirty laundry is cut out, including this, making it a mystery as to why in the movies, Sirius is treated as the first ever successful escapee when it's clear the movie's Crouch Jr. escaped Azkaban without outside help.

** Almost every version skips the King's Cross scene, resulting in some really flimsy logic for why Harry and Ron take the car to Hogwarts. In the [=GameCube/PS2=]/Xbox version, Ginny and the Malfoys leave Flourish & Blotts in the middle of Gilderoy Lockhart's book signing. Literally ten seconds later, Ron bursts in and reveals that the Hogwarts Express left five minutes ago, which raises all sorts of questions. How did Malfoy, Ginny and every other student in Diagon Alley get to the train in time? Why wouldn't Harry and Ron seek help from their new teacher Lockhart, who is standing right next to them? And where is Mrs Weasley -- the one who convinced Harry to go to the book signing in the first place -- and why did she leave one of her kids behind? The PC version has the same problem, but there's at least a loading screen between the two scenes which allows for some time to have passed. The [=PS1=] version doesn't even mention that they missed the train -- they just take the car with zero explanation.

* In general, the movies can't decide if Hogwarts students are allowed to use magic outside of school or not. [[Literature/HarryPotterAndTheChamberOfSecrets Three]] [[Literature/HarryPotterAndThePrisonerOfAzkaban of the]] [[Literature/HarryPotterAndTheOrderOfThePhoenix books]] have Harry getting caught or blamed for using magic at home. As well as these events, the [[Film/HarryPotterAndTheChamberOfSecrets second movie]] has the rule-abiding Hermione magically fix Harry's glasses in public in front of several adult wizards (in Diagon Alley, but even so...) and the [[Film/HarryPotterAndThePrisonerOfAzkaban third movie]] starts with Harry practicing spells in his bedroom as part of his summer homework. While the third could at least be partially justified by the fact that it's schoolwork, the movies have gone back and forth on the issue between "no magic for any reason" to "no magic unless it's for school."