Continuity mistake: In this episode, both Mulder and Scully say that the last time they were in Oregon was 7 years ago. A previous episode this season dealt with the millennium, so we know this episode took place in 2000. So seven years ago would be 1993, the year the show first aired. But in the Pilot episode, the corner of the screen reads their location in Oregon and March 7, 1992. 8 years ago.
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.
Continuity mistake: When Scully is talking to Skinner in Mulder's empty hospital room, her cross necklace is off to the left. Then, when she says, "Sir." it's almost centered. And no, this was not caused by her turning around a minute or so before she said it.
Continuity mistake: Mulder writes Kritschgau's name on the ulnar side of the palm of Skinner's right hand. Later when Skinner is looking for Kritschgau in his apartment building, the writing is on a different part of Skinner's palm, beginning around the middle and extending diagonally towards the thumb.
Continuity mistake: When Skinner walks away from the conference table, his armchair is only slightly turned left from its normal position towards the table, but when he comes back with additional documents, the armchair is turned left to the position perpendicular to the table.
Continuity mistake: After Rob returns to his apartment after throwing out the trash bag with the bloody shirt inside, his mouth starts bleeding and he goes to the bathroom. He removes his false teeth and a few of his real teeth start falling out; he has a small smear of blood on his bottom lip when the camera is looking at him but his mouth is clean when the shot changes to his reflection in the mirror, with no time in between for him to wipe it.