It's always been spyware or another pet. Begin your journey by reading http://windowsxp.mvps.org/ToolsQuit.htm
I have a Dell tower with XP Home Edition that I think is infected with something. I started to suspect something was wrong when Task Manager would close immediately after it was opened. Then we couldn't connect to the internet, I opened the Network Connections window from Control Panel and all that displays are the Wizard icons. I tried reloading the network software from the XP Disk that came with the computer, it acts as if it is loading something but still nothing displays.

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