Harry Jannerone is a Dunder Mifflin salesman from the Dunder Mifflin Syracuse branch located in Syracuse, New York.
After Robert California shuts down the Binghamton branch accidentally when he was drunk, Harry demands to know why Robert did this. Robert doesn't want to let on that he did this drunk and Harry becomes convinced that Robert is crazy. He is also shocked to learn that when the branch closed that no branch inherited the branch's clients and therefore all the clients no longer have a paper/printer supplier leaving them open to competition. Harry also demands to speak to Jim, Dwight and their fictional employee Lloyd Gross. Jim and Dwight get Toby to play Lloyd. This meeting culminates in the two parties getting involved in a war over the most important client. Harry sneaks out to get the client and he ends up in a race against Jim and Dwight. Dwight tries to latch the doors shut with his belt however Harry inexplicably still gets in. They eventually get to the client however it is revealed that Andy had already landed the client. Harry later tells Jim and Dwight as they buy coffee outside of the building that he believes that Robert California is truly going to destroy the company. He drives a Cadillac CTS-V.