Revealing mistake: The first night Ben brings Andie home, he starts the music on the CD player, but no CDs are spinning at all. Yet, the music still plays. He also changes the track mid-scene, and still no CD is spinning.
Continuity mistake: When the guys are looking at Andie's purse on Ben's desk, the two handles are sticking straight up but the close up shot shows the front handle folded over, and then the next wide shot shows them both up again.
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