Windows XP SP2 is save agains trojan horses, hackers, viruses and other intruders but they open up the door for everyone if you share files for your local area network. Here is a quick translation by google, if anyone can translate it in proper english it would be appriciated. As soon as you install SP2 on a Windows XP PC with a certain configuration, your file and printer releases are despite activated Firewall, world-wide visibly likewise all other services. The PC must make only for an internal LAN releases as well as by modem or ISDN a connection available to the InterNet manufacture. DSL users are excluded likewise concerned, those, which already integrated a Firewall in the DSL modem or one DSL-rout use. In addition the InterNet connecting release of this PC must be deactivated. Read More It resulted in test way Scans on the part of the PC world that this configuration is by no means rare or exotic: Without larger trouble and in only short time we found private documents on easily accessible computers in the InterNet. It is to be assumed it weighs their owner in deceitful security that its releases would be visible only in the internal home net, since a password protection was not often even to be overcome. Read the complete story translated by Google at PC-Welt. German link