1. A computer-implemented method for updating contact information in a network with client and server computers, comprising: a. using a computer processor of a client computer, extracting contact information from a memory of the client computer, wherein the contact information is for an addressee from an address book data structure for an address book; b. presenting on a display of the client computer at least one item of extracted contact information for the addressee; c. sending the extracted contact information to a server only if affirmative user input is received in response to the displayed contact information, which extracted contact information causes a computer processor of the server to generate and send over a network to an addressee computer of the addressee a contact information update request; d. receiving, from the addressee computer via the server, updated contact information for the addressee that is generated on the addressee computer; and e. using the updated contact information to update the contact information of the addressee in the memory of the client computer.