Hi Shadowspecter,
The Backweb program is a piece of evil malware that you want to be rid of. When you get the "invalid blah blah" message, write down the name of the program it's referencing, and get rid of it.
For another good removal tool in addition to Spybot, try AdAware SE at
www.lavasoft.com. It's free, and works well in conjunction with Spybot.
For a firewall, try ZoneAlarm, you can get it at
www.zonelabs.com.
If you come across things that Zonealarm or AdAware can't get rid of, try
www.symantec.com, they often have removal tools for the hard to kill bugs.
Good luck