Goof (continuity error): In the episode The Prophet (2.21) Melinda states that Andrea died in a plane crash that occurred on May 11. May 11 is a big day for disasters, as it's mentioned numerous times. Later, in the episode Book of Changes (4.23), Andrea's name is followed with 8204, which reversed is supposed to be her date of death, which would be April 28, not May 11 as previously stated.
Goof (anachronisms): In the Pilot, the ghost of Vietnam Veteran Sgt. Paul Adams is wearing plain Olive drab (green) jungle fatigues, correct for the 1960s, but by the time he supposedly died, it was 1972 and his unit (5th ID), as most U.S. Army units, had changed to the "Nam Leaf pattern" camouflage (ERDL) uniform for several years already.
Goof (crew or equipment visible): When Mr. Dale and Mr. Pinkus are fighting on the porch, both arms of the cameraman and the camera are visible on the right side of the porch.
Goof (continuity error): When first asked about it, the white dove tattoo is behind Julian's right ear. As he's stepping back into Jim, the white dove is visible behind his left ear, where there was nothing before.
Goof (continuity error): Throughout the show, Melinda's car changes between two different years or Jeep. Example: In Voices the car is clearly a newer model Jeep, when she is going to visit someone they show her driving a different year of Jeep
Goof (errors made by characters, possibly deliberate errors by the filmmakers): After an art exhibit Jim states that the last person executed by hanging in the United States was Billy Bailey on September 25, 1996. While he stated the correct person he got the month wrong. Billy Bailey was in fact executed on January 25, 1996.
Goof (factual errors): The sawing a woman in half illusion is just that - an illusion. Though it appears that half of the woman is in one box and half in the other, in fact she is entirely contained in the top box and the bottom box is empty. Therefore, when the magician is spooked by the ghost early in the show and his saw drifts off-target into the bottom box, his female assistant is in no danger whatsoever - she is squeezed up in the top box. But Melinda jumps up and yells, "stop the trick!", the magician draws out a saw covered with blood, and later Jim is seen patching the girl's legs and saying the cuts are only superficial. The magician's saw would never even have been near the girl's legs.
Goof (miscellaneous): Kate Godfrey is incorrectly named Drew Godfrey in the credits.
Goof (revealing mistake): When the cover of Adam Godfrey's book "Lost Delusions" is opened to the first page, the text is actually the first page of William Wharton's novel, "Birdy".
Goof (factual errors): There's a European version of the VW Eos parked in front of Melinda's shop. The car lacked the amber front side markers of the US-version. The episode was shot months before the release of the Eos to U.S. market (August 2006), so a Euro-Spec Eos had to do.
Goof (continuity error): When Melinda enters the elevator she presses the button for the fourth floor, but the elevator stops on the second as seen on the side and she gets out.
Goof (continuity error): The missing toe on the dead guy's body is on his right foot. When the bloody footprints appear at the station house, after Jim's ring is stolen, it's still the right foot that's missing the middle toe. But when Jim points out the footprints to Melinda, as he says 'the missing toe is on the right foot', he's pointing at a print made by the LEFT foot, which is now clearly missing the middle toe; the right foot now has all 5 toes showing in the print.
Goof (continuity error): When Jim and the mortician discuss Bryan's corpse, the mortician first says that the body is a John Doe. Then when Jim asks about the missing toe, the mortician says that there is no mention of any surgery in his records. As a John Doe, he'd not have any records.
Goof (revealing mistake): The light in Ned's room is turned on before Ned switches it on.
Goof (continuity error): The position of the books on the floor and of the firecrackers on the shelf is not the same before and after the starting credits.
Goof (revealing mistake): When Melinda is doing her searches on the Internet, the "Caps Lock" key on her keyboard is lit, but her typing is not in all capital letters.
Goof (continuity error): (at around 1 min) In the scene where Melinda goes to talk to Mayor Millio about postponing the memorial service, the same two extras (one wearing a black sweater with a red stripe, the other wearing a beige sweater) can be seen walking the same path again, and again... and again.
Goof (continuity error): When Jim & Melinda are sitting on the bench in the Square, Melinda's locket disappears between shots.
Goof (boom mic visible): When Melinda is talking to the bartender, the head of the boom mic is reflected in the mirror behind the bar.
Goof (revealing mistake): When Melinda is tidying magazines off the table (just before Eli knocks on the door), behind her you can see Eli's shadow outside the door waiting for his cue to knock.
Goof (continuity error): When 'Sam' and Melinda where talking in the garage, 'Sam' was not seen in the mirror but Jim was.
Goof (revealing mistake): When Melinda and Jim are standing next to the truck talking and Sam's face is reflected in the truck's side mirror, his head movements don't match the movements of his body.
Goof (revealing mistake): When "Sam" is investigating his old computer looking for clues to his forgotten life, he enters the "Sent" folder in his email program. While there is one email sent by him to his former girlfriend, "nicole72", subject: "I know you're mad", the rest of the emails *sent* by him are mostly spam, including an email that Sam would have sent to a Randel2012 at 3:28am with the subject, "100 mg 60 pills $2.17 per pill".
Goof (crew or equipment visible): When the red bus goes by, the camera crew is reflected in its side.
Goof (continuity error): When the camera pans from the water to Eli he's barefoot yet right before he gets ready to jump in he takes off his socks.
Goof (revealing mistake): When Emma is trapped on the attic, and she is banging on the door and pulling it, so someone would free her, the door opens a couple of inches.
Goof (errors made by characters, possibly deliberate errors by the filmmakers): When Melinda and Aidan go to see Jim/Sam at work his photo ID isn't Sam's face, it's Jim.
Goof (errors made by characters, possibly deliberate errors by the filmmakers): Jim/Sam is in the stairwell talking on the phone to Melinda, and just as they are wrapping up, another doctor says, "Dr. Clancy, got a minute?" No one knows he is Jim Clancy. Everyone sees and knows him as Sam Lucas.
Goof (factual errors): When the Ghost Surgeon is operating, a Heart Monitor with red LED displays is seen. The date of the Surgeons death is found out to be 1959. The first practical LED however was invented by Nick Holonyak, Jr., in 1962.
Goof (revealing mistake): Towards the end of the episode, when Caroline Mayhew ehlps the screaming girl onto the wagon, Sean scares the horse making it go crazy. The stunt double (playing the little girl) is hanging off of the wagon and her legs nearly touch the ground or edge of the wagon. Then all of a sudden, you see the little girl hanging from the wagon. You can tell the difference in size between the stunt double and the little girl.