Make sure that you are using version 126.96.36.1996 (Critical Fix 2) and higher of KAV & KIS as they are only compatible with Windows 7.
Main advantages of the new Windows 7 compatible KIS 2010 & KAV 2010:
- Seamless integration with Windows 7
- Superior levels of protection
- Unrivaled performance on Windows 7
- Support for new features in Windows 7
- Technical support for users of KIS 2010 & KAV 2010 installed on Windows 7
Visit Kaspersky Windows 7 Page
You can Upgrade to latest Kaspersky 2010 for Free if you have a licensed copy.