In the TV version, when they changed all instances of Darian's name to Adrian, they forgot one part. At the end, Nick is going through the dozens of letters she has sent him. The return addresses say Darian, or D. Forrester, etc. (see trivia)
When they first show the bag of wasps (honeybees) you can see the nest. When Adrian shakes it to dump them the nest is gone.
Near the end, when Cheyenne leaves Nick's apartment, the "Kryptonite" deadbolt is not installed on the door.
Color of Alicia's underwear as she walks out of the bathroom. When she is in the bathroom they are a beige/nude color full cut underwear. However when she gets to the bedroom a few steps later they are blue bikini bottom style. Then without pause she walks in front of the closet and removes the top and has nothing underneath it.
In the closet scene, when Darian/Adrian exposes herself to Nick, she pushes her hair up with both hands. But in her close up, her hands are nowhere near her face.
When Nick is sanding his car, he is using the wrong side of the hand sander. He is sanding it with the side that is the handle.
Obvious stunt double when Adrian and Nick are fighting by the stairs.
When Adrian and Nick are fighting by the stairs at the end of the movie, the wooden pole that Adrian is swinging bends.
When Adrian/Darian is on the swing talking to Nick, his actor, Cary Elwes, accidentally goes out of his American accent and into his real-life British one.
Given Adrian's past history, it beggars belief to think that she would be matched with a young male therapist.
When Darien is playing the piano at the party, her hand movements are not consistent with the piece that is being played.
When Amy goes to her car after her night with Nick, she meets and talks to Adrian. On the DVD version, right before Amy says, "Let me explain something to you," Amy's voice is heard saying, "Adrian," but Amy's mouth clearly does not move.
When Cheyenne is coming up the stairs to talk to Nick about Adrienne, you can see the shadow of the square corner of the camera moving up the steps on the right side in the moonlight.
At around 16 min., the camera's shadow is cast on the party guests.
When Amy is developing a print in her dark room, she is surprised to see a photo of Darian. But she would already know what was on the print as she would have already exposed it from the negative using an enlarger.
A central component of the film's climax is the carousel that Adrian's father, Cliff, has been working to restore for many years. How has the weight of such a large fixture not caused it to go crashing through the attic floor?
Early in the film, while talking about Nick's writing, Adrian notes, "You have such a terrible time with the objective case." Later, Adrian has her own trouble with the objective case when she says, "I think it's brought Nick and I a lot closer." She should have said, "I think it's brought Nick and me a lot closer."
When Adrian refers to a man as an embezzler, Nick corrects her to add alleged. It was already established at that time he had been convicted. After conviction a crime is no longer considered to be alleged as guilt has been proven beyond a reasonable doubt in a court of law.