It's known to Spybot S&D author
Please see http://spybot.info/en/news/2006-01-07.html
I don't have System Works 2006 though. All I have is Norton Internet Security 2006 and it doesnt give me message on incompatibility of the software to Spybot S&D.
I know an elderly man who from time to time asks my advice concerning his computer. (XP home)
He tried to download the Norton System works upgrade from his 2005 version to 2006.It failed repeatedly, he didn't give me details on the error messages but finally a message appeared on his screen that Norton 2006 System Works was not compatible with Spybot S&D and he needed to remove Spybot.
After removing Spybot all went well and he was successful with the upgrade.
Is there a question here? Well I would like to know if anyone else has run into this, I had nagged this cautious old guy for a year to get some spyware protection and I finally managed to talk him into Spybot and Adaware and now this!