In order to upgrade Kaspersky Anti-Virus 2009 / Kaspersky Internet Security 2009 to version 2010 you have to do the following:
Download the distributive of Kaspersky Anti-Virus2010 / KasperskyInternet Security 2010 from the Kaspersky Lab’s official site http://www.kaspersky.com/productupdates
Run the downloaded distributive and install the latest version of Kaspersky Anti-Virus 2010 / Kaspersky Internet Security 2010 “over the top” of the already installed product.