Continuity mistake: Every 4 episodes the table in the living room changes completely, one episode it's a huge oval table, in another it's a medium-sized round table, in another episode it turns into a very small round table, some times it's even a large egg shape.
The Life and Love of Joe Coogan - S3-E17
Other mistake: When Rob, Buddy, Sally, Joe and Mel are all showing up after they played golf at the beginning of the episode if you look at the window all the background there is flat as heck. But trees do not increase in elevation that quickly in flat ground. Unless you're in the mountains.
The Bottom of Mel Cooley's Heart - S5-E19
Other mistake: All the extra people in the back aren't talking. There is one pair of people at the table near the wall behind Rob and Mel that keep glancing at them and look very uncomfortable. (00:11:00 - 00:13:00)
Continuity mistake: Rob is in the garage on his motorcycle. We notice the door to the garage leads out to the back/side yard towards the house, but in "Long Night's Journey into Day" the door to the garage is connected to the house from the kitchen.
A Vigilante Ripped My Sports Coat - S4-E5
Continuity mistake: Right before Rob starts the story to Sally and Buddy about how Jerry ripped Rob's sports coat, the box is on the floor. When we cut back to Rob, Buddy and Sally later on. The box isn't even in the room anymore. Then later on when Mel comes to pick up the box, it's back on the floor again.
Other mistake: Richie has Rob's electric razor from Richie's bathroom. Rob and Laura have a bathroom for themselves... Rob doesn't need to put his stuff in Richie's bathroom.
Factual error: Rob told Sally and Buddy that he hit "Boom Boom" in the appendix. When we see Rob punch that guy he hit him right in the upper stomach. Rob would have won the boxing match. Because "below the belt" refers to all the area of the body that lies below the line of the opponent's navel, including the groin area, legs, and crotch.
Revealing mistake: While Rob is having a boxing match and Laura is really mad at Rob. I noticed that some of the punches are actually to the hand region when Rob is in the corner and supposedly gets a boxing glove to the face. They aren't hitting each other that hard either.
Other mistake: Laura and Rob do not like having guns in the house and Laura is terrified about having them in the house... Yet in this episode... There are 2 guns in the basement displayed right next to a giant deer head on the Cross beam in the middle of the room up high. Neither of them care that the guns are there.
Harrison B. Harding of Camp Crowder, Mo. - S1-E6
Factual error: This is the only episode that Harrison is seen, mentioned or even talked about. But in all the rest of this series there is no Harrison. Both Harrison and Rob mention that he was the guy on the spot light fir the shows... But not one time did we see a spotlight on Rob in any of the episodes.
Other mistake: Rob's watch is completely blank. No numbers, no hands or the knob to adjust time. His watch is fake. (It may be that way in all the episodes but this is the first time I noticed it so far).
Continuity mistake: When we first see Richie at the beginning of the episode he has extremely dark "bruises" all over his hands, arms and face. But by the end of this episode all the bruises are gone except for 1 which is on his face below his left eye (on our right). Bruises do not just vanish in 2 or 3 days if they are that bad.
My Husband Is Not a Drunk - S2-E6
Other mistake: If Rob is that easily hypnotized then when Rob's friend hypnotized Millie he would have gone out light a light same when he did Laura and Jerry. Rob would have been out right then and there for all 3 of them... Not just when he did Buddy.
The Sound of Trumpets of Conscience Falls Deafly on a Brain That Holds Its Ears - S3-E11
Other mistake: Rob is complaining to Sally and Buddy about this couple running through a parking lot not looking where they are going, and they knocked him down on his rear end as well as hands. He fell into some grease yet there weren't any grease stains on his jacket which would have actually been on his butt and hands.
Continuity mistake: Laura is reading the name of Rob's book "Unimportant Life of Robert F. Petrie" yet in "Fifty-Two, Forty-Five or Work" Rob said his name was "Robert Simpson Petrie"
Continuity mistake: In this episode we do not see a garage door. Yet in the "Long Night's Journey into Day" episode the garage door would have been right where all the tools and junk were on Rob's right (close to where Richie was standing talking to Rob).
Fifty-Two, Forty-Five or Work - S5-E13
Other mistake: Right at the beginning of this episode Rob says "9 years ago right in this office... I just came on as head writer 2 months was all... Buddy, Sally and I were sitting at this desk, writing a sketch, and you (Mel) came in with some special news." (so on and so forth with that line.) Rob, Sally and Buddy weren't in "this office" building... Didn't even have the same desk or furniture.
Long Night's Journey into Day - S5-E23
Other mistake: Rob tells Jerry to keep calling Rob's house. Jerry says "hello, this is Jerome Helper" yet there was the episode "All About Eavesdropping" where Rob calls Jerry "Gerald."
Other mistake: Sam tells Rob "Laura could be late because of the rain". Yet neither Sam, Laura, Millie or Clark had any wet clothes, jackets, hats etc. Rob was the only one that had gotten soaking wet. Also when looking into the window he taps on the glass with a white glove (which he didn't have on when he got into her house).
Other mistake: Millie tells Laura (in the USO women's house) "I can't keep a boyfriend" yet she's been "married" to Jerry and they get along somewhat OK.