Continuity mistake: In the shot of the 6th Precinct police station, it has a California state flag flying out front. The episode took place in Massachusetts, at the Massachusetts Institute of Technology. (00:07:45)
Schizogeny - S5-E9
Continuity mistake: After her father is pulled out of the window, Lisa leans out and there is no glass left on the sill, she even places her hands on it. Later when Mulder and Scully look at it, there is all sorts of jagged edges on the sill. (00:16:35 - 00:20:00)
Continuity mistake: When Fox Mulder is having the flashback when Samantha was abducted, he looks at the doorknob, in the close-up he is still looking at the doorknob but it has changed colour.
Continuity mistake: Scully's FBI badge number that she gives to the phone company is different to the one she gives in season 4's "Teliko". (00:02:05)
Continuity mistake: The dates on the academic discipline and progress forms for Max are not in accord with the order of the episode, coming after the "Millennium" episode. Supposedly the changes in his behavior and grades started a few months before, but the reports are from a few years ago. (00:24:55)
Continuity mistake: After Mulder has been released from the containment cell, and he and Scully go back to his room, the items on the table change position in between shots. (00:15:00)
Continuity mistake: When Dr. Kendrick/Eve is talking to the two little girls and she's clearing up the mess on the table, the position of the straw changes between shots. (00:29:55)
Kitsunegari - S5-E8
Continuity mistake: How was Modell tried and convicted in 1996 if he only woke up six months ago? Six months before this episode would be at least mid 1997. (00:06:05)
Field Trip - S6-E21
Continuity mistake: At Mulder's 'funeral' around when there is a knock at the door, we see Frohike raise his bottle to take a swig. The shot cuts to facing Scully and we can see Frohike further in the background and his bottle is nowhere to be seen, when he should've been mid-swig.
Continuity mistake: General Callahan tells Mulder that the man he saw in his office said his name, but all he said was, "Your time has come, killer". (00:13:10 - 00:17:25)
Continuity mistake: When Senator Richard Matheson tells Mulder about the four Japanese Nationals had been murdered, he says that the murders had occurred several weeks ago. But when Mulder brings Scully up to speed a scene or two later, he tells her that someone must have been able to identify the four doctors who were performing the autopsy because they were murdered YESTERDAY. (00:30:05 - 00:33:10)
Kill Switch - S5-E11
Continuity mistake: In the same season episode "Unusual Supects" Fox Mulder's file lists him as Fox William Mulder. The A.I. discovers a similar file but the name is just Fox Mulder.
Continuity mistake: General Callahan, who is referred to as General Callahan throughout the episode by Mulder, gets called "Lieutenant" Callahan in the last scenes in the steam-room, while lying on the floor.
Continuity mistake: When Martin takes out the nanny-cam from the bear, the lens-protection is on so the camera could not have recorded anything. (00:30:00)
Continuity mistake: When Mulder and Scully first see the artifact rubbing in Skinner's office, the rubbing is quite faint and lightly done. A couple of times during the episode, the rubbing becomes darker and heavier drawn.
Continuity mistake: When Scully arrives to investigate the kid who was crushed by the bleachers the time stamp says 5:10AM. It seems strange that the investigation would start the next morning, unless the high school holds basketball practice at 3:00 in the morning. (00:16:35)
Continuity mistake: If the Kernoffs were really devoted Catholics why would they have waited six years to have Dara baptised? (00:00:40)
Answer: As he stated many times throughout the series, Mulder needed Scully to be sober and skeptical. Whenever Scully's skepticism wavered and she started questioning her own rationality, Mulder would try to restore her sense of skepticism, because he needed her to be clear-thinking.
Charles Austin Miller