Continuity mistake: During the diner sequence, the amount of fries in Harry's basket changes between shots.
Continuity mistake: At the snow owl benefit, Helen raises her hand as Nicholas is introducing Carl. In the next shot which is the opposite angle, her hand is down, and she repeats the action, but with a drink in her hand.
Continuity mistake: During the snowball fight scene at the ski resort, it's either snowing or not depending on the angle. In one shot it's sunny. The first two shots showing just Harry feature snow. Cut to Mary and it's not snowing.
Continuity mistake: When Harry sits down on the toilet and lifts up his legs, his eyes are closed, and they remain closed until the very end of that particular shot. Then, when it switches to the front shot of Harry a few second later, his eyes are open, right from the very beginning of that shot. And if you look closely at that shot change, you don't see Harry do the action of opening his eyes - they just change instantly between the shots.
Continuity mistake: In the Unrated Version DVD, in the van sequence after Lloyd's second encounter with Seabass in the restroom, Harry says that he will stop talking about Lloyd's encounter with Seabass. Lloyd turns his head and looks over at Harry. Then it switches to a close-up on Lloyd from the other side, and we see him repeat the same action of turning his head and looking at Harry, this time more sharply.
Continuity mistake: Lloyd reads the article about Mary and can't even pronounce the word "the", yet when Harry says look on the briefcase for her name, he says "Samsonite" with no problems, and Lloyd can easily read the "Man Walks On The Moon" newspaper headline in the hotel bar.
Suggested correction: That isn't a continuity mistake - it is meant to be funny or ironic... or part of the "dumbness." Humor is often comprised of violations of expectations. He can read a big word like "Samsonite" but not a three-letter word like "the." (Less likely, it is also plausible that he didn't actually read the word "Samsonite" but recognized it as a name-brand symbol).
Continuity mistake: When Harry is speaking to the girl at the gas station, he tells her he's going to Aspen and she takes the cigarette she is smoking out of her mouth. When the camera pans to a front view of her jeep in the next shot, the cigarette is back in her mouth and she takes it out again.
Continuity mistake: When Harry and Lloyd first arrive at the truck stop, you can see a man with a white hat leaving the diner after the 18-wheeler passes by. Later on in the scene, the same man is about to exit again.
Continuity mistake: The film appears to begin in the summer. Look at the outside shots in Rhode Island when either Harry or Lloyd are driving; green grass and many leaves on the trees. As they travel further west the landscape appears to be fall. Then finally in Colorado it appears to be the dead of winter.
Factual error: When Lloyd drops Mary off at the airport, he watches her leave and then hits a parked car, inflating the airbag. First, the Cadillac Brougham Lloyd is driving was never available with a driver-side airbag, and secondly airbags are not designed to inflate after such a low-speed impact.
Continuity mistake: When Sea Bass demands to know who hit him with a salt shaker in the diner, we cut back to Harry and Lloyd's table and Lloyd begins pointing at Harry. When the camera angle changes, Harry turns around and Lloyd begins pointing a second time.
Other mistake: On the subtitles for the UK "Uncut" DVD (I'm not sure if this applies to other "Unrated/Uncut" DVDs), the subtitles mix up the character names during one shot. As Lloyd goes in the wrong direction, the film cuts to a shot from behind the pair. Harry says that he "expected the Rocky mountains to be a little rockier than this." The subtitles incorrectly state that this line was said by Lloyd. Lloyd's response that "John Denver is full of shit" is also incorrectly attributed to the wrong character; the subtitles say Harry said that.
