I don't know if you've seen the troubleshooting information on the Spyware Blaster page (click here).
You might try checking the permissions on your firewall if you have one.
More likely, it says here (click here), it says there's a bug in version 3.3 which sounds similar to your problem. They've got a workaround you can try, and hopefully there should be a solution soon.
Hope this helps,