Shortly after installing IE6, I was having trouble opening some FTP sites that my friends were not having problems with. One of them was able to come up with a solution. In Internet Explorer 6.0, I needed to place a checkmark in the box next to "Use Passive FTP (for firewall and DSL modem compatibility). This option can be found under Tools | Internet Options | Advanced | Browsing. This was due to the fact that I was using a router and Zone Alarm for my cable modem with Windows XP.