Factual error: Redford's character speeds towards his office in Langley, Virginia driving his Porsche. As he passes a Georgian style building and the camera position, road markings (zig zag lines, metal road studs and a 'keep left' bollard) are all momentarily visible. This very short scene was obviously filmed on a UK road, certainly not in the US. (00:08:30)
Audio problem: When Harry Duncan calls Muer at his house in the opening of the movie you can see that he is talking on a cellular phone in an elevator, yet when he hangs up (you hear it from Muer's end of the line) you can hear the sound of a phone receiver being slammed down. Cellular phone calls end with a polite little beep, there is nothing that makes a physical noise like that. (00:09:05)
Factual error: The "American Consulate in Hong Kong" is actually the HSBC building. The actual consulate building is nearby, but perhaps not so photogenic.
Factual error: In Suzhou Prison, presumably the Suzhou near Shanghai, all the prison guards are speaking Cantonese, which is a southern dialect. They should be speaking either Mandarin (Putonghua) or their regional dialect.
Factual error: At the end of the movie it is about 7:42am in Langley, Virginia. In Suzhou, Tom Bishop is being rescued out of the prison and as he is being flown away you see sunlight poking down through the clouds in the backdrop. It would be 8:42pm there. Since they showed the Berlin wall falling on the news that would put the film at the beginning of November in 1989 where it would be dark at 9pm.
Other mistake: During the scenes in Beirut, we see a picture of a militiaman firing an RPG at an armored vehicle. If you look at the launcher, you can see that there is no grenade in the launcher when it is "fired."
Factual error: There would never be a US Embassy in Hong Kong - only a consulate.
Factual error: Part of the movie is set in Beirut during 1985. Periodically, there are scenes with Robert Redford's character working from a command post in the American Embassy. Behind him, is a quite modern looking 15" monitor. The interesting part is that although the monitor looks out of place, the makers of the movie saw fit to fill the screen with monochromatic "green" information, which would be consistent with 1985.