The One With The Dirty Girl - S4-E6
Corrected entry: When Ross is kissing the dirty girl on her sofa, he calls her Sarah. Then, when he kills the rat on her coffee table and thinks it was her hamster, he calls her Shelley.
The One Where Underdog Gets Away - S1-E9
Corrected entry: In this episode, when Chandler is telling Rachel his Thanksgiving story, he says that he had just had a mouthful of pumpkin pie when his parents told him they were getting divorced. However, in 'The One With All The Thanksgivings', in the flashback, Chandler is eating turkey when they tell him (hence the houseboy saying 'more turkey Mr. Chandler?').
Corrected entry: In the airport Ross says "I really thought she'd stay". After he says this when the camera zooms out the cut between the carpet and the set floor is very visible. (00:19:50)
Correction: This is not a mistake; terminals are set up this way, carpeted at the gate and tiled in the walkways.
The One With Monica's Thunder - S7-E1
Corrected entry: From the start of Series 7 (and for the next 2 series' at least) does anyone else notice the change in Matthew Perry's voice? I've searched to see if anyone else has mentioned it and as far as I can tell, no one has, but to me it's very obvious. I'm not sure I can explain it too well, but there's just something in his voice that changed (the tone of it and overall sound); it sounds like a different person talking.
Correction: Matthew Perry stopped smoking during the run of the series. He apparently was a very heavy smoker. This most likely accounts for the change in his voice. In any case, this isn't a 'mistake' in the first place.
The One With The Worst Best Man Ever - S4-E22
Corrected entry: In the scene where Joey tells Ross that the stripper stole the wedding ring, when Chandler says, "So you might say, it's a magic ring", you can see Joey starts laughing in the background. In the next shot he starts laughing again. (00:12:30)
Corrected entry: In the scene when Phoebe gets back to the beach house, she is pouring herself a Margarita and instantly she goes from pouring it to holding it up.
The One With All The Thanksgivings - S5-E8
Corrected entry: In shots of Ross in Monica's living room there is a table behind him. In one shot you can see the shadow of the pole from the boom mic on the cloth that is covering it. (For a split second only.) (00:04:05)
The One With Ross's Inappropriate Song - S9-E7
Corrected entry: When Chandler finds the video labelled 'Monica' in Richard's appartment, Monica mentions that Chandler could never grow a mustache. However, in earlier episodes (around series 2), he does grow one, trying to copy the same Richard (granted it's not a very good one)
The One With The Blind Dates - S9-E14
Corrected entry: When Monica tells Chandler that she'll be ovulating until the sixth, he's crouching next to Emma, but then the shot cuts and he is standing up.
The One In Barbados, part 2 - S9-E24
Corrected entry: In Barbados, while playing ping pong, balls magically appear.
The One After Joey And Rachel Kiss - S10-E1
Corrected entry: Towards the start, when Chandler, Monica and Phoebe are listening through the walls, when they are listening to Rachel and Joey, and the camera slides "through" one room to another, you can see Phoebe's hand in front of the wall section that is in between the two rooms.
Corrected entry: The foosball table must be magical - the chick and duck double in size after they're rescued as compared to when Joey first shows Phoebe earlier that day. (00:05:30)
The One With All The Thanksgivings - S5-E8
Corrected entry: In the scene where Phoebe is describing her worst Thanksgiving experience (in 1862 as a nurse) and her left hand is blown away, you can see that the hand is fake as it doesn't move, is shorter and is a different color to the right one. Additionally, in the time between the bomb exploding and her hand being torn away, a rope is visible moving it.
Correction: Yes, that's the point, the arm does look obviously fake, and just look at the way blood spurts out, it looks deliberately cheesy. Arms don't just fall off like that either. It is just a funny scene. The writers had no intention of it being taken seriously.
The One With The Memorial Service - S9-E17
Corrected entry: Phoebe says she called Mike by using the speakerphone on the base unit. All fine and dandy, except how did she dial his number? The number keys are on the phone Monica took.
Correction: Many base unit models have number key pads and also a redial key.
The One With Rachel's Other Sister - S9-E8
Corrected entry: Just before Rachel pushes the plate off of the table, you can see Jennifer Aniston look behind her to check the position of the plate. It's really obvious.
The One After Joey And Rachel Kiss - S10-E1
Corrected entry: In Rachel's hotel room, there is a door on the left of the wall that joins onto Monica and Chandler's room. Due to the layout of the rooms, the only place it could lead to is Monica and Chandler's room. However, when Ross is talking to Rachel and she's looking for Joey, she walks through this door and has a quick look around. Surely she would see Joey in there, or at least Monica, Chandler and Phoebe and ask if they knew where Joey was?
Correction: The door that leads to Monica and Chandler's room is on the right of Rachel's bed - we see Joey get dragged through it, and the camera pans "through" it shortly afterwards, when all the friends are listening to Ross and Rachel. Rachel looks through a door which is on the far left of the bed; this is presumably the bathroom. Rather bizarre it doesn't occur to Rachel that Joey might have just gone through the other door, but she's never been the brightest woman.
Corrected entry: Matthew Perry was so famous for missing his mark while taping that he developed the backward slide that you see him do in almost every show. He would come bounding into his scene slide backwards looking down for his mark and then hit it. (Per the tour guide at Warner Brothers Studio).
Correction: Matthew Perry has never done a backwards slide on Friends.
The One In Vegas, Part 1 - S5-E23
Corrected entry: When Phoebe is looking at herself in the mirror with Joey's gladiator hat and says that she should start wearing hats, the microphone's reflection is visible at the top of the mirror.
The One With The Red Sweater - S8-E2
Corrected entry: Chandler and Ross go back to the reception site to take pictures with disposable cameras to "replace" the cameras they had misplaced. Chandler is posing, smiling, etc. In the previous season, Chandler and Monica are getting their engagement picture taken and Chandler can't smile for the camera. In fact, Monica ends up taking her picture with Joey and puts that in the paper.
The One Where Chandler Can't Remember Which Sister - S3-E11
Corrected entry: When Rachel is eating at the diner and she and Monica are talking, there is a red glass sitting in front of her. In the next shot she is talking to Mark and says "It's not funny!" and the glass is gone; in the shot after that it's back again.
Correction: Actually, he calls her Cheryl both times, which is the correct name of the character played by Rebecca Romijn.