
Continuity mistake: In episode 10 (Joey's Place) the Tanner family move Joey into the garage, redecorating it so the entire place is filled with Joey's furniture, but in this episode it shows the characters in and out of the garage which is completely empty and back the way it was before Joey moved in. Later in the episode Joey's stuff is out of the alcove again.

Continuity mistake: When Opie surprises Andy by telling him that he wants to take piano lessons with Clara, he heads to the piano to play what he already knows, and when Opie plays Chopsticks on the piano he's wearing a different shirt.

Plot hole: When Dominique is on TV, she says she got the shoes from Al's store. Then the Amish guy comes out to confirm she broke her leg from the shoe he made. Al says yes. She got the shoes way before Al knew he had no more shoes and before they even hired the Amish guy. How can she break her leg from his shoe if he wasn't hired and making them yet?
Suggested correction: Al was passing the blame.
The correction above is correct.

Character mistake: When Hoss takes Timmy for a horseback ride, after they both dismount by the lake, Hoss calls Timmy by his real name Johnny (Whitaker) and not Timmy.

All Hell Breaks Loose (1) - S2-E21
Continuity mistake: Before the Roadhouse fire, Ash and Dean are talking on the phone. Ash looks at his watch, on his left hand, it says 8:10, and has a black dial/face. As Dean and Bobby go through the rubble, Dean identifies Ash by his watch. Still on his left hand, it is now upside down, evident by the crown of the watch (used to move the hands of the watch) which previously facing his hand, is now facing his elbow. Also, the dial/face of the watch is now silver instead of black. This is a different watch, and was inadvertently put on the burnt arm upside down.

Chapter Two: The Weirdo on Maple Street - S1-E2
Factual error: When Steve and Nancy are making out, the intro to "A Hazy Shade of Winter" by The Bangles plays. While the original version of the song was released by folk-pop duo Simon and Garfunkel was released in 1968, the version heard here was released in 1986, 3 years after the scene takes place. (00:52:30 - 00:55:40)

Continuity mistake: Right at the beginning of the episode a Cadillac Escalade gets stolen. The car is the newest model. The chase begins and the car is a new model right up to a scene when they crash into some other cars. That part was filmed with older model Cadillac. The damage is quite severe, but the chase continues again with the new model that has only one bit of damage - a mirror that has come apart.

Other mistake: When McNulty uses the stopwatch to rob a bank, he goes through a small wooden door and past the employees. With time frozen, the small door should have stayed open but immediately swings shut.

The Treaty - S4-E7
Factual error: At the UN conference, 'England' is shown as a member of the Security Council. England sits on both the UN and the Security Council as part of the 'United Kingdom' - not as a stand-alone country. UN nerds Leslie and Ben would have known this.

Continuity mistake: The scene is shot in a traffic jam on the freeway. The sky has a gray overcast. All close up shots of the irate female driver were filmed in a studio - the background is flat and is a vivid blue. (00:04:00)

Star-Crossed Lovers and Other Strangers - S1-E16
Visible crew/equipment: When Rory asks Lorelai to call Emily to get her out of Friday night dinner so she can celebrate her and Dean's 3-month anniversary, a boom mic drops into the shot as Lorelai stands to get the phone. (00:07:05)

Plot hole: They're in the Clam complaining that they can't drink when they make the revelation that Brian can because he's technically 56. But Quagmire should be able to drink, as in a much earlier episode, he's revealed to be over 60.
Suggested correction: Quagmire considers the rest of them to be his best friends. He isn't drinking because they can't drink. He is complaining because since his friends can't drink - he won't drink, so he is still pissed.
It's still a plot hole considering Quagmire's age. I think the writers messed up big time.

Deadeye Dick - S5-E9
Visible crew/equipment: In the scene where Trampas says, "You can bet no matter what happens, I will be blamed for it," as Sara Lane turns to ride away you can see a Chevy truck for about four seconds. The time left on the counter is between 29 and 28 minutes.

Continuity mistake: When Kitty comes downstairs to give the gang cookies, she tells Eric that she picked out an outfit for him to wear on career day. He then turns and mouths the words "Help me." In the next shot you can see Jackie sitting on Kelso's lap when in the previous episode, she broke up with him. In the next shot she is standing behind him. (00:01:00)

Factual error: In Oregon and New Jersey, state law requires that a gas station attendant pump the gas. Romero pulls into an Oregon gas station and encounters a nosey person. They are both pumping their own gas.

Revealing mistake: When Sgt. Troy throws the grenade at the Gestapo agents barricaded behind the table, it is thrown wide right, yet the pyrotechnic explosion is dead center of the table barricade.

Audio problem: Season 3, Episode 68, "The Duel". Sometimes the tank's co-axial machine gun is firing, but no gunfire sound is heard.

The Friendly Physician - S2-E29
Plot hole: The scientist yells for Igor to capture the escaping Castaways, to which Igor responds "capture them yourself" in Ginger's voice. The scientist appears surprised to find out Igor is not Igor, but how can this be? He had to be the one to pull the lever to switch everyone's personalities and bodies around, so he should have already known.

Family Ties - S1-E22
Visible crew/equipment: After Rygel's transport pod returns to Moya, as the docking bay door slides open, in the shot facing everyone while they have their weapons drawn we can see the bare floor. However, when Aeryn checks Crais for hidden weapons and then as D'Argo approaches him, there's a blue crash mat on the floor. Then it vanishes again.