E-mail address lookup

I upgraded my Notes client 6.5 to Notes 8.0 Basic edition in windows XP. When I click new message and type the e-mail address, it lists several various address for a same name like

John Jeffry john.jeffry@xxxxxxx.com

john.jeffry@xxxxxx.com

John Jeffry/xxxx/xxxx

From where it is fetching the e-mail address? I checked in my local address book and server address book and no matching found for the above name. What should I do to display the addresses only either from my local or server address book…?