Hi
I seem to have the same problem on my home pc for the last week or so. It is XP Professional with IE6 SP1.
Thankfully I have just solved it.
Do you happen to have Kazaalite installed at all? >:-<
If yes, you may remember as part of the setup process, you had to replace your HOST file with the Host file supplied by KazaaLite. If you look at the HOST file in notepad you will see that many of this add server addresses are pointing to 127.0.0.1 which is of course your own machine so they cannot be found.
If you have lost the origianl HOST file this is what it should say.
Hope it solves the problem, it did for me...
# Copyright (c) 1993-1999 Microsoft Corp.
#
# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.
#
# This file contains the mappings of IP addresses to host names. Each
# entry should be kept on an individual line. The IP address should
# be placed in the first column followed by the corresponding host name.
# The IP address and the host name should be separated by at least one
# space.
#
# Additionally, comments (such as these) may be inserted on individual
# lines or following the machine name denoted by a '#' symbol.
#
# For example:
#
# 102.54.94.97 rhino.acme.com # source server
# 38.25.63.10 x.acme.com # x client host
127.0.0.1 localhost