Joe Stewart of SecureWorks has developed a simple test which reveals at a glance whether or not a system has been infected with one of the wide-spread versions of Conficker. The new test is based on the fact that Conficker blocks access to various security and anti-virus pages. It includes a page that shows images of normal and of blocked sites. If certain images are missing on the test page as shown, the system is likely to be infected. Conficker.A doesn’t block DNS queries, so the test is not suitable for environments like corporate networks.”]
Source: http://www.h-online.com/security/news/item/Simple-Conficker-test-for-end-users-740933.html