Continuity mistake: At the Buckingham estate, when Mrs. Buckingham tells Ronald that Mary is driving back from the country, there are three statuettes on the table behind the sofa, with the center one beside the box, but when it cuts to the closeup that statuette has vanished. (00:15:20)
Continuity mistake: When Harold's manuscript is wrapped up and tied with string, we see three closeups of the front with large black writing. The first closeup is when Harold holds it before he leaves, second when Mary holds it while on the train, and third when Roger Thornby holds it before opening it. The problem is there is no writing whatsoever on the front of the wrapping in all other shots. (00:24:00 - 00:38:25)
Continuity mistake: After Harold rips up the envelope with the check, when Uncle Jerry takes one of the pieces to light his pipe we see the ripped piece in his hand in the closeup, but when Harold and Jerry find all the pieces, that piece Jerry used is ripped differently than in the first closeup (not the burned edge at the left). (00:52:35)
Continuity mistake: When Harold sees Mary's wedding announcement in the newspaper, in the closeup we see two photos of Mary and Ronald with Mary on the left and Ronald on the right, but in the wideshot as the paper droops from Harold's hand, the photos are different and the left photo is of a male. (00:54:25)
Visible crew/equipment: When Harold steals the bootlegger's car with the flowers and hidden alcohol in the back seat, after the first bottle pops as he drives past some stores, we can see in the window reflections the crew's car pushing Harold's car while filming this shot. (01:02:05)
Revealing mistake: When Harold jumps onto the rear of the fire truck, the cable attached to him at his chest can be seen during the stunt. (01:06:25)
Continuity mistake: Upon learning that a friend is about to be married to a wealthy man who is still married to his first wife, Harold races to the man's mansion to halt the wedding. Driving a wagon pulled by two horses, he passes the Western Costume Company which was then at 7th and Figueroa in Los Angeles. After passing through a series of tunnels on the road that is now part of the Harbor Freeway, Harold again goes past the Western Costume Company.
Other mistake: Throughout the movie, Harold Lloyd's prosthetic glove on his right hand is noticeable in the wideshots when he stretches or holds out his right hand, so in all the closeups showing both of Harold's hands it's the stand-in's hands we are seeing.