Blooper

(at around 9 min. into the film) When Mattie enters her apartment at the beginning of the film, she is wearing blue jeans. Then, while reading in bed, she is wearing light brown slacks. During her walk from her bed to Izzy's room, she is wearing the light brown slacks again and then, suddenly, she is wearing the blue jeans again.

(at around 1 hr. 13 min. into the film) When Mattie arrives in the servers' room, the PC unit is black with two rolls of red duct tape near it. She turns around and in the background, the PC unit is white with two rolls of red duct tape near it, then it is black again. The position of the chair near the table also changes.

When the "Help Me" messages appear on the screen during the group online chat session, the appearance of the text goes from "Help Me" to "HelpMe" between shots.

(at around 21 min. into the film) When we see the first instant messaging conversation between Stone, Izzy, and Tim, Tim's screen name is "Tim86". However, when Tim starts talking to Stone (at around 40 min. into the film), it has changed to "Tim79".

In the beginning of the film, you see a group of guys looking at a laptop, and later in it, you see the same group of guys sitting in the same place looking at the same laptop with the same windows open.

(at around 55 min. into the film) There is a typo in a screen user interface. There is a list of results with "Douglas Ziegler", but the last entry (#5) says "Zeigler, Douglas". The "i" and "e" are reversed.

(at around 13 min. into the film) Although the film is set in Ohio, Mattie is shown coming from an underground subway system. Columbus, Ohio does not have an underground subway system.

The film is supposedly set in Ohio; however, the telephone area code (818) for the rental office of Josh's now-vacant apartment is actually for the San Fernando Valley, California area (and the surrounding areas). Furthermore, Ziegler's Columbus Zip Code should be 43201 (not the made-up 41273) and 7th Avenue street numbers only go as high as the 3600s (not 13124), plus the actual street is not full of multi-storied apartment buildings designed in the Eastern Bloc brutalist architectural style. Dexter's Weymouth Drive street address (from his bounced check) is fictitious, but its Zip Code (44101) is an actual one in Cleveland, Ohio.