I've found a lot more *grins proudly to herself*
Here u go.....
Marcus Flint, 8th year student?
First, go to the Quidditch chapter of Sorcerer's Stone.
On pg 185, bottom half of the page in the paperback version, the book tells us that Marcus Flint is the Slytherin Captain in his sixth year.
That means Harry's second year is Marcus Flints seventh and final year at Hogwarts.
In the Harry's third year, the Prisoner of Azkaban, the Quidditch Final chapter, page 306, fourth line, Wood and Flint shake hands.
HOLD ON! This year would be Flint's eighth year. You are only supposed to go to Hogwarts for seven! An arguable error indeed, J.K. Rowling has since clarified that Flint has held back a year, which makes sense considering Flint's character.
Headmaster Albus Dumblefore?
In chapter twenty-two (pg 428), Owl Post Again, close to the end when Harry and Dumbledore are talking in Lupin's office after he left, J.K. spelled Dumbledore's name as Dumblefore. This is found only in American First Edition books.
Dark Mark, Where?
In the Goblet of Fire, when Harry gets stuck in the stairs and Snape and Moody comes along, Moody makes some statement. I forgot what it was, but it was something pertaining to the Dark Mark on Snape's arm. Snape suddenly grabs his right arm, therefore the mark should be on that arm. But later, he shows Fudge the mark on his left arm...
Slytherin, Ancestors or Descendents?
Not quite halfway through the final chapter "Dobby's Reward" in Chamber of Secrets, Dumbledore explains to Harry why he can speak Parseltongue. In this explanation, he refers to Lord Voldemort as "the last remaining ancestor of Salazar Slytherin." He quite obviously means descendant, not ancestor, unless the Slytherin family reproduces differently from the rest of humanity.
Snape or Snap?
If you look on page 285 of the Prisoner of Azkaban, in the chapter "Snape's Grudge", on the second line from the bottom of that page you will see Snape's name spelled as "Snap"! Found in first American Edition, Hardcover.
Chess Lessons
In 'Through the Trapdoor' in book 1 Harry, Ron and Hermione take the place of the chess set pieces. Ron takes the place of a knight but when it comes to him sacrificing himself to the queen he only takes a pace forward. Knights cannot move just 1 pace forward.
Confused Clock
In Book 2, the Weasley's clock shows phrases such as Feed the Chickens but in Book 4, it only states the locations of family members. We may be able to conclude that the Weasleyes have two clocks. In book 2, the clock is described as hanging on the wall and in book 4, it is the 'old grandfather clock'. Grandfather clocks aren't known to hang on walls.
Stupid Seeker?
In one of the books, the Slytherin Keeper makes a foul during a Quidditch match, but J.K. marks it as "a foul on the Slytherin Seeker".
Perry Weasley?
In the Goblet of Fire, when Harry gets stuck in the stairs and In Chamber of Secrets, the paperback, on page 157 after PERCY says "Get--away--from--there--" his name is misspelled as "Perry". It's on line 11 from the bottom.
Nearly Headless Nick is Nearly 500
In book 1, it is almost Nearly Headless Nick's 400th death day (years since he died). But in book 2, he celebrates his 500th deathday.
Charlie works in "Rumaina"
In book 4 (English Hardback), it states that Ron's brother Charlie works with dragons in "Rumania" surely this should be "Romania". It is found on chapter 5 first page on line 21.
Bill Weasley: Left Hogwarts When Harry Came?
In the 4th book, Bill Weasley says that he has not been to Hogwarts in 5 years. Since Harry is in his 4th year, that would conclude that Bill had left the school the year before Harry joined Hogwarts. This cannot be true because Bill is the oldest child of the Weasley family. Charlie (the second oldest) is younger than Bill, but he was not at school when Harry was. Charlie probably left the school at least three years before Harry came. We can determine this because Fred and George were talking about how they had not won a single game since Charlie left (Fred and George said this in Harry's first year). They probably would not have been talking as though Charile had left the year before. This was pointed out to J.K Rowling, she said that Bill visited the school for one of Charlie's Quidditch matches.
Priori Backwards
In book number 4, when Priori Incantatem is preformed, the spells that Voldermort's wand cast out are all the people he has killed, from his most recent to his first. However the mistake made is as follows: James Potter appears first out of the wand, followed by Lily Potter. This suggests that Lily was killed before James, which we know for a fact is not true.
Sorry... that was a long one.... oh well
(by the way... I
do have a life.....)