Continuity mistake: When Angela is listening to Ben Franklin talk about flying his kite, her drink is near her lap, but in the next shot she's taking a sip from it.
Continuity mistake: Michael and Dwight arrive at Wallace's house and discover that Michael is dressed like the servants, so they choose to exchange shirts. Behind the catering van, Michael removes his jacket and throws it on Dwight's shoulder, who grabs it and puts it between his legs. The frame switches from front to side, showing Michael removing his tie and hanging it on the van's mirror. When the frame goes back to front, Michael is shown still with his tie on, and throwing the jacket again, missing Dwight. (00:05:41)
Launch Party - S4-E3
Continuity mistake: In 2-13 "The Secret" Pam and Jim are talking about how Jim used to have a crush on Pam when she first started here. This implies that Jim was working here when Pam was hired. However, in this episode Pam says that when Jim first started working there she said, "Enjoy this moment, because you're never going to go back to this time before you met your desk-mate, Dwight." These two scenes contradict each other.
Launch Party - S4-E3
Continuity mistake: The way the numbers on the sales board are written by Andy change in between shots. (For example, the "305" is written differently, but still "305"; not that it becomes a "380" when Andy changes the number).
Branch Wars - S4-E6
Continuity mistake: Earlier in the show we see Michael trying to get Jim to go on a "sale" to crush Utica by pumping him up in the conference room and when he turns to leave he sees Toby in an orange bow tie for The Meeting of the Finer Things Club but later in the episode we see Toby wearing a greenish/brown tie. (00:07:00 - 00:11:00)
Survivor Man - S4-E7
Continuity mistake: In "The Alliance" (1-4), Pam says that the next office birthday is Meredith's, but it isn't until the next month. Later, in "Survivor Man", it is said that Meredith's birthday is at the end of 'Birthday Month', when many employees have birthdays close together. It wouldn't be possible for Meredith's birthday to both be the next office birthday but also at the end of the following month, which is stated to have many other birthdays in it.
Continuity mistake: When the Dunder Mifflin lawyer says "she thought it had to do with her recent breast enhancement surgery," the woman on the right side of the screen has her hand on her forehead. Then the shot changes angles and the woman's hand is now resting on her chin. (00:08:45)
Baby Shower - S5-E3
Continuity mistake: When Jan lets Michael finally hold Astrid, she has a pacifier. When Michael gives her to Phyllis, Astrid's pacifier is gone.
Continuity mistake: When Meredith's hair catches fire, we never see her face (as it's a stunt double). After Dwight uses The Fire extinguisher on her, the shot cuts (although she is still in the frame) and her hair is different, as it is now the original actor that plays Meredith. (00:05:50)
Continuity mistake: Michael's scarf is above his collar in the first shot, but moments later, seemingly without moving, his scarf is tucked below his collar. (00:06:40)
Lecture Circuit: Part 2 - S5-E15
Continuity mistake: When Jim and Dwight are talking about the activities for Kelly's party, Dwight is attempting (horribly) to blow up a silver balloon. Just after Jim finishes reading The List of proposed activities, Dwight says, "You're right, forget horse hunting, it's stupid." Immediately after he says this, the shot changes and he is now holding a brown balloon. (00:16:30)
Continuity mistake: When Kevin is writing Pam a check, he flips it open so the check register is folded under the checks. After he says "wait till Monday", the check register is no longer folded under the checks.
Continuity mistake: When Dwight is talking to the kids, he picks up one fry. In the shot of him from behind, he's holding two fries. It goes back to one fry when he takes a bite.
Continuity mistake: When Jim is outside comforting Pam after she finds out her mother is dating Michael, he begins to explain a mallard recording device that Dwight gave to him and used a big hand motion that put his hand in the air. In the next shot, the hand that was in the air is now gripping his coffee cup.
Double Date - S6-E8
Continuity mistake: In Fun Run (4-1) when Michael hits Meredith in the parking lot, it is said by him that it was on company property, but in this episode Pam says that the hit in the parking lot will be off company property.
Continuity mistake: When Michael begins the conversation with Jo, the door behind him is closed. After a few lines, the door is open. (00:19:10)
The Manager and the Salesman - S6-E15
Continuity mistake: When Michael enters the room he messes with Jim's hair and Jim's hair is noticeably different, however a few different camera angles later Jim's hair is back to normal even though he couldn't have possibly had time to touch it. (00:09:10 - 00:09:50)
Continuity mistake: When Jim and Michael are in the conference room with Jo, Michael messes up Jim's hair. A few shots of Jim later, his hair is nicely combed again.
Continuity mistake: When Jim reveals the tiny desk underneath his "Quad-Desk" to Dwight, Dwight sets his briefcase down on a chair not shown in any previous shot. (00:21:05)
Happy Hour - S6-E20
Continuity mistake: When Michael is doing press-ups Angela is sat, then she stands to see what's going on - away from her chair, it cuts to another shot, and she is sat down again.
Answer: In the 2007 episode "Ben Franklin" when Jim is talking to Pam there is a candy bar with a purple wrapper that says "Picar-" I assume picaroon, it's hard to see past Pam. I found this trying to investigate what that candy bar is lol.