Zone Alarm
I started using Zone Alarm at the suggestion of
www.grc.com about 4 years ago. I upgraded to ZA Pro about 2 years ago, for the popup blocker, and then started to get a variety of problems, like the VSMON problem. Check the Internet experiences (horror stories) at grc.com, and why he recommends a GOOD firewall. He also will let you test your firewall. I'll have to check out the most recent update to ZA to see if it's worth getting rid of the intermittent problems. Take care.