Jamie gets mugged in Amsterdam and Jenny mentions that all their passports were stolen. While it is now possible to travel between the Netherlands, Slovakia, Germany, Italy without any passport controls, this was not possible in 2004. Slovakia ratified the Schengen Agreement in 2004 but it wasn't in effect until 2007 (for the other countries it was actually possible).
When the four friends are in a French restaurant and Scotty, Cooper, and Jenny are trying to persuade Jamie to join them on their quest to Germany, Scotty's line is heard as "I Love Denmark," but his mouth form the words "I Love Amster..." as if he was in the process of saying Amsterdam before the shot changed.
As Scott and Cooper walk towards "The Feisty Goat" Scott says that there is no drinking age in Britain. This is not true - the minimum age to buy alcohol in a pub is 18, but from the age of 16 you can have one unit of alcohol with a meal in a restaurant.
When in London, Scott and Cooper are standing on the South Bank of the River Thames - the river is behind them and behind that is the Palace of Westminster. Scott nods "towards" the Tower of London and Buckingham Palace - in actual fact, both of these landmarks are behind them.
During the robot battle scene a boy is seen to the right of the three other main characters. This boy is also the same boy sitting to the right of Burt when the news is reporting the arrival of the new pope, Scotty, and Burt says that he is going to record this.
The type of airplane changes during the departure scene. First you see a Lockheed L-1101, then a Boeing 767 and finally the inside of a Lufthansa-jet. Lufthansa doesn't own any type of the previous aircrafts.
When Mieke reads Scott's reply to her proposal to come to America, several words have been added or changed. For example, the clearly visible phrase "you sick German freak" has changed into "you sik German fraek".
When Cooper meets up with the rest of the gang after going to Club Vandersexxx, his bag strap moves to different places over the writing on his t-shirt between shots, first slightly over-lapping the "V", then moving further across the text.
When Scott and Cooper are in the red double-deck bus on their way to France and Scott asks the hooligan where they are going, the bus goes under a viaduct or bridge. In the next shot, there is no trace of the viaduct or bridge.
When Scotty and troop arrive in Rome, Scotty says "Here it is" while pointing at the Summer at Sea building. In the next shot, they are walking up to the Vatican doors. (There was originally a scene between the two that was deleted.)
The word "zusammen" which Scott checks up in the dictionary doesn't even occur in the shot of the e-mail. Afterwards at the close-up of the word another version of the letter is shown. The translation he reads aloud skips three sentences of what is written.
In the station scene where Cooper is checking out Jen's butt, when she turns around to talk to him, her hair is wildly curled and styled. When she is being hit on by the club owner just seconds after, her hair is dramatically less curly.
When Jenny, Jamie, Cooper and Scotty are at the house party after Graduation, Jamie has a spill on his shirt. When he gives Jenny her drink, the spill is a different shape then later when they are walking through the party, past the pool and at the keg.
When Scotty is behaving like a robot, right before he and the real robot fight, he does a move that the robot says "isn't a real robot move". Right before that, a guy gives Scotty money and Scotty has his leg down. In the next shot, his leg is up and he's putting it down to thank the guy.
During the party when Cooper peaks through the bushes and glimpses Candy topless, she's resting in the pool. In the next shot, he quickly steps into the pool, and Candy is sitting up with her hands across her chest, as if anticipating him. There was not enough time for her to realize Cooper was there and to shield herself.
During the party, when the song "Scotty doesn't know" begins and Fiona is dancing, she takes off her sweater and throws it into the crowd. In the next shot, you can see her shoulders and she is still wearing the sweater.
When Madam Vandersexxx writes the safe word on the piece of paper, we can clearly see she uses handwriting, but later when Cooper looks at the paper we can see that the safe word is written in printed letters.
Scott's last name. His actual last name is Thomas. However, in the beginning when Mieke is reading her email and speaks in German the subtitles state his name as "Scott Thompsen." Also, when he is on the train reading his emails from Mieke the name in the "To" field was Scott Liebier.
Almost the whole movie is shot in Prague or other cities in Czech Republic. They filmed almost all locations at famous tourists places, so everyone living in Prague can clearly see it's not Amsterdam, Paris or anything else.
When the group arrives in Paris, they are clearly standing in front of a famous Czech concert hall. While waiting in line at the Louvre, they are standing on the side of the same building, with several other landmarks in Prague visible behind the robot.
When Scott and Cooper are initially at the US airport leaving for London, the camera pans past a road sign consisting of a blue circle with a red border and a red X through the middle. This is an international "No Stopping" sign, but at a US airport "No Stopping" signs are simply rectangular signs that read "No Stopping Any Time".
When the group arrives in northern France, we see a long shot of what is supposed to be Crans-sur-Mer, a seaside city there. St Tropez's orange and yellow cathedral is very obvious in the centre of the shot.
During the opening credits when director Jeff Schaffer name appears, a map of Europe can be seen with flags for each country. The Republic of Ireland is shown to have the colors of the Union Jack of the United Kingdom (of which RoI is not a part) and not the green, white and orange colors of the Irish flag.
Near the end the camera pans in over Oberlin University, where Scotty is starting college. The shot shows a river right in front of the college. In reality there is no river anywhere near the campus of Oberlin.
Tourists are not allowed into the sacred sites in the Vatican wearing tank tops or shorts (which can be seen on the sign near the entrance), however Mieke (among others) manages to get in, dressed as such.
During the scene in the Vatican, one of the characters tolls Saint Marcus' bell accidentally and then sets the Pope's hat on fire, while the other tosses the hat to the fireplace, sending white smoke out of a chimney and finally appearing in a balcony in front of a crowd in Saint Peter's square. As all these elements are located in different buildings (the Pope's apartment is in the Apostolic Palace; the bell and the balcony are in Saint Peter's cathedral and the chimney belongs to the Sixtine Chapel), so the scene is impossible.
Scott and Cooper travel to Paris on a Double Decker bus from London. A Double Decker bus is too large to be admitted on either the cross Channel ferries, or on the Eurostar train. This would make crossing the Channel impossible.
The courier service offers to fly Scotty and Cooper to London. However, they are seen as flying on Lufthansa, Germany's national airline, who does not fly directly to London from anywhere except Germany, their intended destination.
During the scene at the Vatican, a TV news reporter begins his coverage stating "I'm coming to you live from Vatican Square..." Actually, the true name of the place is St. Peter's Square. Another square, more modern, adjacent to it and slightly smaller is called Pope Pius XII sq.
At the other nude beach one of the ladies is translated as saying "the statue is very moving". The girl rubbing her shoulders replies, "Oui" (which means "Yes"), but it is translated as saying "Let's make out". However, this is clearly an attempt at humor by the filmmakers.
When tourists arrived to Bratislava (the capital of Slovakia), the town looked like a zone of military operations or armed conflict. There was neither war nor conflict in Slovakia, it's a peaceful and not at all a poor country. However, this movie is a parody of how Americans view different parts of Europe. Nothing in this movie comes close to accurately representing real European locations. This was an attempt at humor, not an attempt to accurately represent Slovakia.
When they get to England it is 10.40 am, which would make it the middle of the night in the United States. However, depending on deadlines, it would not be at all unusual for a partner at a law firm to request files in the middle of the night, and certainly not unusual for a partner to be in the office by 5:40 am (assuming the characters live in the Eastern Time Zone and Eastern Time is currently five hours behind London).
When their flight home from Rome is called, they are still in the check-in area. For an international flight they should have checked in, cleared customs, and passed through security before their flight was called. In a busy airport like the one in Rome, they will be lucky if they make it to the gate in time to board the flight.
When Scott reads Mieke's emails in the train, the third paragraph of the first email reads, translated from German: "Sandra, how do you like your new job as a real estate agent", in which the reader is addressed in first person female form. This paragraph has obviously nothing to do with the movie whatsoever.
At the beginning of the film, there is a map of Europe with most of the countries coloured in with their flags. However, Ireland is given the Union Flag (the flag of the United Kingdom), when in fact only the most northern part (Northern Ireland) is part of the United Kingdom. The rest is a separate country and should have been coloured in Irish colours.
On the train with the freaky Italian guy, the train is traveling from right to left. Scotty is sitting on the left hand side of the compartment but he looks out the window and claims he sees the "big tunnel" but this is in the wrong direction he is looking in, Jamie then looks in the wrong direction to see the "big tunnel" which they are going into.