In this episode Joey and Alex are watching a commercial advertising Joey's appearance on "The Ellen Degeneres Show" the next day in which we see Joey walking across the stage and hugging Ellen. The next day when Joey goes to tape the appearance on Ellen, she says "Nice to meet you" and he replies, "It's nice to meet you too" implying that they've never met. But we had just seen them interact in the TV commercial, showing that they had in fact met before.
Joey puts the manila folder down on the desk and in the next shot it is back in the tray, then in the next shot it is back in Joey's hands.