Norton Internet Security 2011 Upgrade

I got a message to upgrade to NIS 2011 and so I clicked on the button and started the upgrade. Then it told me that I needed to uninstall or remove my Spy Sweeper program because it was incompatible with NIS 2011.  Somewhere I read to uninstall my NIS program and reinstall it and so I did that but I got the same error message to uninstall my Spy Sweeper program.  I want to finish installing my NIS 2011 upgrade without uninstalling Spy Sweeper.  How do I do this?