"If you are blocked from loading the remote images in
the first row of the top table above (AV/security sites) but not
blocked from loading the remote images in the second row (websites
of alternative operating systems) then your Windows PC may be
infected by Conficker (or some other malicious software).
"If you can see all six images in both rows of the top table,
you are either not infected by Conficker, or you may be using a
proxy server, in which case you will not be able to use this test
to make an accurate determination, since Conficker will be unable
to block you from viewing the AV/security sites."